Pressurized Coolant + Oil Blowby Help/Thoughts

PhillipisHappy

New member
Hello,

Long time lurker first time poster.
I have a 2006 Dodge Sprinter 2500

259,XXX miles on it now

I bought it with 237,XXX

I have driven it from the SF bay to Montana and back 3 times, up to Seattle and back once and it has never given me any issues other than a few old hoses that cracked/split and a turbo resonator that needed to be replaced.

I had to top it off with coolant here and there, and some oil every now and then, for a 14 year old van I figured its just par the course.

Just within the last week things have gotten bad for me.
I had a coolant hose break, so I went ahead and replaced them all with hoses I got from Europarts-SD.
Then I had a few of the hoses shoot off, I thought I just didn't tighten the clamps down enough so I tightened everything down.

Then the seam on my radiator gave out and would shoot out coolant when I put the van under heavy load 2,800+RPM with sufficient boost.
No idea when the last time the radiator was replaced so I bought a new one and put it in. Everything appeared good as I drove around town.
I hit the freeway to see if any hoses would give out, gave the van a good push and then the low coolant light came on and my heart dropped.

I pulled over and opened the hood - exact same coolant pattern around the seam of the tank, no coolant anywhere else it had to have broken the seal on the plastic tank again. Now I figure I've got a bigger problem.

If I baby it and keep it below 2,500 RPM and low boost pressure I don't have any problems, but driving like a grandma pisses off everyone around me.

My coolant system is getting pressurized. I found TROLL's thread and his videos on youtube. My symptoms appear to be the same as much as I wish this wasn't the case I think I have a head gasket failure.

Then just a few days after this I opened my oil filler cap and oil started sloshing out. This has never happened before, I have topped off my oil with the van running before and all was well. There is some light white vapor coming from the oil filler cap and dipstick if I remove it.

I talked to Vanski since he posted that he is from the East Bay - where I live - and he put his number up. Very helpful guy, I told him what I am experiencing and he said it is almost certainly a HG and possible the whole head will have to be replaced if the warping is bad.

1.5-2k if everything goes good, if its opened up and other things are wrong looking at 4-6k for a rebuild. Or 8-9k to get a used motor dropped in.

**QUESTION**
How long can I drive with my engine like this and how bad is it for my van? Will it potentially damage other systems costing me more money?
The van has never over heated, and once it loses some coolant it sort of just stays there, but once I add more to top it off and turn the light off it shoots it out after some time.
I had a road trip planned that I saved up for the entire year and this all happened the week I was planning to leave.
The trip will be about 2,000 miles. This is a loaded camper van.

I figured if it will hold out and work for the 2,000 miles and I can fix it when I get back that would be awesome instead of losing my engine and my trip.
If the engine is already on its way out (Not sure if it is?) is there any harm in driving it as it is now and coming back to rebuilding it or dropping a new motor in after the trip?

I realize this is not the right way to do things and I may be playing with fire, I'm just not very knowledgeable and that is why I decided to stop lurking and post for the first time. I've spent the last 4 days reading different threads and my head hurts. I wish I was more mechanically inclined and I would have just ordered the HG and got started on a tear down, but I really can't trust myself with anything like that. I've only ever changed a starter, replaced this radiator, and changed my fluids along with some other bolt on bolt off parts like a viscous fan clutch and water pump.

I have receipts from the previous owner that the injectors were replaced, head was machined and valves were ground, so It sounds like he just did the HG not too long ago, there is no mileage for the head, but injectors were at 234,XXX miles. What could cause a failure so quickly?

Thanks for your time and sharing all your wisdom.
 

Nautamaran

2004 140” HRC 2500 (Crewed)
If you’ve searched here for HG failures, you’ll have likely already seen Dennis/lindenengineering’s posts on how important cooling maintenance is.
If the previous owner had a gasket failure, it’s possible (likely?) that they had an overhead episode that warped the head? If the cooling system wasn’t properly maintained you may have blockages in the cooling passages of the block, creating hot spots, and leading to warping and leaks.
Leaving coolant in the block too many years, or mixing incompatible antifreeze can cause issues too.
Running a citrus flush through the engine may clear any blockages, which might help even out your big temperature swings. And don’t kid yourself: if you’ve had broken coolant hoses while running hard, then you have almost certainly dried out the head and had localized overheating.

Can you run as-is? Maybe?? Since your head has already been decked once you likely already need a new one. I’d add a catch bottle to the overflow hose, then keep the expansion tank up near the MAX mark, but remember you should never open/depressurize the system while hot, since the coolant will subsequently boil earlier - until allowed to cool back to ambient temperature. (Check the coolant in the morning. System may still have pressure, due to HG blow-by)

-dave
 

koenb

Active member
If it were me, I would not drive it another 1/4 mile let alone 2,000miles :2cents:. I'm sure others with engine rebuild experience will chime in here about the head being previously machined and the inadvertent risk associated with it.
 

jrod5150

Well-known member
Head gaskets blown on the exhaust side can last for quite awhile. It just depends on how badly its blown. If you baby it you can keep chugging. of course a steep hill etc be prepared to pull over when the gauge rises. I had a client van that I drove from oakland to LA with no overheating or having to pull over this was mild weather though and it made it up the grapevine fine. Yours pressurizing so badly that your busting hoses is pretty significant. if you haven't changed a starter or a radiator Id highly advise you not to start pulling the head off. If the head was already done you may want to reach out the shop that did the work. Its possible they could be more giving since they did the job and it didnt seem to last as long as it should have. As the post above says, lack of maintenance kills the cooling system and simply fixing the gasket issue and not addressing the cause of the high temps is just destined to repeat failure.
 
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PhillipisHappy

New member
If you’ve searched here for HG failures, you’ll have likely already seen Dennis/lindenengineering’s posts on how important cooling maintenance is.
If the previous owner had a gasket failure, it’s possible (likely?) that they had an overhead episode that warped the head? If the cooling system wasn’t properly maintained you may have blockages in the cooling passages of the block, creating hot spots, and leading to warping and leaks.
Leaving coolant in the block too many years, or mixing incompatible antifreeze can cause issues too.
Running a citrus flush through the engine may clear any blockages, which might help even out your big temperature swings. And don’t kid yourself: if you’ve had broken coolant hoses while running hard, then you have almost certainly dried out the head and had localized overheating.

Can you run as-is? Maybe?? Since your head has already been decked once you likely already need a new one. I’d add a catch bottle to the overflow hose, then keep the expansion tank up near the MAX mark, but remember you should never open/depressurize the system while hot, since the coolant will subsequently boil earlier - until allowed to cool back to ambient temperature. (Check the coolant in the morning. System may still have pressure, due to HG blow-by)

-dave
How quickly can a head warp? When my hose blew off I only drove about 2 miles and kept it at 20mph. Temp gauge sat at 220-230. I wasn't going to hard at the time, this was after changing all the hoses so some were looser than they should have been I suppose and this is when the pressurized coolant problem really started to show its head.

I've never had the van overheat, it holds temperature very well.
I don't have any issues of heat coming from the heater core, could there be blockages anywhere else?
I did find that the metal pipe coming from the upper radiator hose that goes along the bottom of the radiator was completely plugged up like 100% solid when I got the van. But I drove it like that for a bit before finding that out and the temp never shot up, the needle stayed going right through the 8 on the 180 mark.


I just flushed my engine twice. Once with Thermocure once with Prestone and flushed about 5 times between each with straight water.

I have always used Zerex G05 with distilled water, but I have no way of knowing what the previous owner used.
I've read what you said about not opening/depressurizing the system while hot, someone else mentioned this in a different thread.
What are the problems associated with this?
 

PhillipisHappy

New member
Have you checked your radiator cap? If it's bad high coolant pressure can blow hoses.
Old radiator cap was actually quite loose, when I put the new one on thats when it blew my tank open so I think the loose cap was preventing pressure from building too much. Cap I bought is 20psi. I just ordered a Mercedes cap, but they are only 18 PSI. The pressure I'm experiencing isn't a 2 psi difference.
 

PhillipisHappy

New member
If it were me, I would not drive it another 1/4 mile let alone 2,000miles :2cents:. I'm sure others with engine rebuild experience will chime in here about the head being previously machined and the inadvertent risk associated with it.

What sort of risked are involved with driving a machined head? I haven't read anything about that yet. I have been driving for almost 2 years no problems, just some coolant topping off here and there. But now its getting ugly.
 

PhillipisHappy

New member
Head gaskets blown on the exhaust side can last for quite awhile. It just depends on how badly its blown. If you baby it you can keep chugging. of course a steep hill etc be prepared to pull over when the gauge rises. I had a client van that I drove from oakland to LA with no overheating or having to pull over this was mild weather though and it made it up the grapevine fine. Yours pressurizing so badly that your busting hoses is pretty significant. if you haven't changed a starter or a radiator Id highly advise you not to start pulling the head off. If the head was already done you may want to reach out the shop that did the work. Its possible they could be more giving since they did the job and it didnt seem to last as long as it should have. As the post above says, lack of maintenance kills the cooling system and simply fixing the gasket issue and not addressing the cause of the high temps is just destined to repeat failure.
That's some relieving news that perhaps I can grandma my way through this trip.
My gauges are actually very stable, I just loose some coolant and having the little light on bugs me.

I'll be hanging around the coast mainly so the weather is milder.


The first hose is the only hose that actually sprung a leak, it was the one running from the EGR to the circulation pump.
I replaced them all preemptively because of that one breaking, the rubber was definitely getting old.
Hoses have not come off since the first few slipped off, I tightened them down good, but obviously that pressure had to go somewhere and its either out the top of my radiator cap, or this time it split my plastic tank at the seam.

Some of the few things I have changed are a starter and a radiator. My old radiator busted at the seam, so I thought it was just because it was old. I put a new one in and same thing happened.

I've got no plans to pull the head off, I know thats way beyond me.

I tried reaching out to the shop that did the work, but its just a generic receipt with a phone number, doesn't look official at all. To my surprise someone answered, but their english was pretty poor, it was hard enough for me to get him to understand that he had done the work already and not that I wanted work done.
 

Nautamaran

2004 140” HRC 2500 (Crewed)
I have no experience to guess how fast a head would warp, only know the theory behind how it happens. Google “line heating”: a metal section is heated and expands, stretching and cold-working adjacent cooler sections. The cool section then stays longer and stretches the hot section as that area is cooled... reheat and repeat. It was once a common technique for forming compound curves in ship building, and I’ve watched 3/4” steel plate worked into domes using this process.

As for why you mustn’t depressurize the coolant, it’s due to flash point and the formation of bubbles in the coolant within the engine. Bubbles are TERRIBLE at soaking up heat: fluid is literally hundreds of times better. Removing a hot rad cap is like removing the lid if a warm cola bottle: tiny bubbles form throughout the system, coating all the internal surfaces. These tiny bubbles combine into large bubbles, and the adjacent metal surfaces don’t cool as efficiently. Keeping the fluid under pressure allows it to absorb more heat without vapourizing, which allows it to soak up heat more efficiently.

Finally, the pressure that builds in the cooling system is mostly a result of fluid expansion, not vapour pressure. It’s why there’s an expansion tank.
So once you release the pressure, the system will not repressurize unless the fluid boils, but this creates even more bubbles. The only way to restore operating pressure is to allow the system to cool. The coolant contracts as it cools, the expansion tank can then be filled if necessary, and the system “burped” of any remaining gas bubbles.
The good news is that if your head gasket is leaking then the system has an alternate source of pressure: the leaking combustion gasses. The bad news is that the gas bubbles being introduced into the coolant do a terrible job of soaking up heat... and if the rate of flow of combustion gasses into the coolant is too high you’ll wind up blowing the coolant right out of the engine and/or the radiator cap.
Note that a properly operating rad cap is a pressure relief device, and should not allow the pressure to climb much above its set point. So with combustion gasses entering it SHOULD release and prevent the pressure from climbing. You certainly should not be cracking radiator components unless the valve is failing to release.

-dave
 
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vanski

If it’s winter, I’m probably skiing..
Hey Phil. Good chatting the other day.

I was under the impression the radiator expansion tank (top part where the cap is located) completely split on you twice. If you’re getting coolant coming out of the cap there is a good chance you have a faulty cap. Given the low cost of this item, it’s worth a shot to fully examine Have you tried the rubber glove test I mentioned?:


since you mentioned costs we discussed I feel obligated correct (no biggie in the mistakes).

if there are no stuck injectors, or glow plugs, the timing chain looks good, etc, etc, etc and the head is verified good via simple straight edge check via an engineers straight edge - $2.5k.

if the head is bad but salvageable (unlikely since it seems to have already been machined) - add $1.2k

new head - add $2k and that’s if it’s non oem

if an injector is stuck and needs to be wasted add $550 per fouled injector

from there it’s all T&M for whatever else could be an issue; glow plug issues, sloppy timing chain, what else should be done while I’m in there?, etc,etc, etc.

I have a source where I can find good used motors. They’re typically in sprinters which are drivable to verify the he health of the motor. Usually $3k for the motor plus all the time acquiring it and R&R.... $4.5-$6k total.

As discussed, even though I can’t really do a head gasket job right now due to living in my shop due to a home remodel going on, I could take a look at your rig and tell you what’s going on with it and the severity.. Hit me up.
 
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vanski

If it’s winter, I’m probably skiing..
Btw... the cap does more than just cap the coolant system.. it also regulates pressure.. so you can blow hoses and things with a malfunction cap. Here’s to being optimistic!!!
 

PhillipisHappy

New member
I have no experience to guess how fast a head would warp, only know the theory behind how it happens. Google “line heating”: a metal section is heated and expands, stretching and cold-working adjacent cooler sections. The cool section then stays longer and stretches the hot section as that area is cooled... reheat and repeat. It was once a common technique for forming compound curves in ship building, and I’ve watched 3/4” steel plate worked into domes using this process.

As for why you mustn’t depressurize the coolant, it’s due to flash point and the formation of bubbles in the coolant within the engine. Bubbles are TERRIBLE at soaking up heat: fluid is literally hundreds of times better. Removing a hot rad cap is like removing the lid if a warm cola bottle: tiny bubbles form throughout the system, coating all the internal surfaces. These tiny bubbles combine into large bubbles, and the adjacent metal surfaces don’t cool as efficiently. Keeping the fluid under pressure allows it to absorb more heat without vapourizing, which allows it to soak up heat more efficiently.

Finally, the pressure that builds in the cooling system is mostly a result of fluid expansion, not vapour pressure. It’s why there’s an expansion tank.
So once you release the pressure, the system will not repressurize unless the fluid boils, but this creates even more bubbles. The only way to restore operating pressure is to allow the system to cool. The coolant contracts as it cools, the expansion tank can then be filled if necessary, and the system “burped” of any remaining gas bubbles.
The good news is that if your head gasket is leaking then the system has an alternate source of pressure: the leaking combustion gasses. The bad news is that the gas bubbles being introduced into the coolant do a terrible job of soaking up heat... and if the rate of flow of combustion gasses into the coolant is too high you’ll wind up blowing the coolant right out of the engine and/or the radiator cap.
Note that a properly operating rad cap is a pressure relief device, and should not allow the pressure to climb much above its set point. So with combustion gasses entering it SHOULD release and prevent the pressure from climbing. You certainly should not be cracking radiator components unless the valve is failing to release.

-dave
I appreciate you taking the time to write this all out, I'm getting a better understanding everyday the more I read.
Thank you.
 

PhillipisHappy

New member
Hey Phil. Good chatting the other day.

I was under the impression the radiator expansion tank (top part where the cap is located) completely split on you twice. If you’re getting coolant coming out of the cap there is a good chance you have a faulty cap. Given the low cost of this item, it’s worth a shot to fully examine Have you tried the rubber glove test I mentioned?:


since you mentioned costs we discussed I feel obligated correct (no biggie in the mistakes).

if there are no stuck injectors, or glow plugs, the timing chain looks good, etc, etc, etc and the head is verified good via simple straight edge check via an engineers straight edge - $2.5k.

if the head is bad but salvageable (unlikely since it seems to have already been machined) - add $1.2k

new head - add $2k and that’s if it’s non oem

if an injector is stuck and needs to be wasted add $550 per fouled injector

from there it’s all T&M for whatever else could be an issue; glow plug issues, sloppy timing chain, what else should be done while I’m in there?, etc,etc, etc.

I have a source where I can find good used motors. They’re typically in sprinters which are drivable to verify the he health of the motor. Usually $3k for the motor plus all the time acquiring it and R&R.... $4.5-$6k total.

As discussed, even though I can’t really do a head gasket job right now due to living in my shop due to a home remodel going on, I could take a look at your rig and tell you what’s going on with it and the severity.. Hit me up.
Thank you for correcting those costs.
I am going to try the glove test in just a moment here I'll post my results. After reading hkpierce's linked thread I see the engine should be warm because of the nature of some cracks only showing up at certain temps. Gaskets should show a leak right away, but a head crack or warp will only show up at certain temps. The advice I read was to warm it up with the cap off. To be clear I can drive the van with the cap off? That is the only way to really warm the van up, it will never reach temp at idle.

Your are correct that I did have a split on the plastic expansion tank on my radiator.

I guess it depends on how quickly that pressure is building, if I drive it like a grandma and boost slowly I may get some or no overflow from the cap.

If I drive it like I stole it hard and fast then that is when coolant shoots out of the seam on the tank. Its not a complete split in that the tank is now in two pieces, but coolant definitely comes out from the seam where the two pieces meet. This happened on the old radiator and the new one I put in.

I have my new OEM MB cap from Europarts-SD, admittedly I am a little hesitant to put it on as I feel like the pressure build up may be too much. This older cap is loose and provides some pressure relief.

Like I said I will try the glove test soon here and I will post my results.
I will give you a ring, I'd love to have you check it out since you've been around so many of these motors.


EDIT:

I just tried the glove test, but the engine was cold.
I revved it to about 2,500 RPM's several times for a few minutes, but the glove never filled.

I followed hkpierce's link and read that the engine should be warm. I will try it again with a warm engine. I read that a cracked/warped head will only show itself at certain temps when the metal is allowed to expand where as a HG will be noticeable pretty immediately.
The advice was to warm the engine up with the cap off. To be clear it is ok to drive my van with the radiator cap off? The van will never reach temp at idle.
 
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jrod5150

Well-known member
That's some relieving news that perhaps I can grandma my way through this trip.
My gauges are actually very stable, I just loose some coolant and having the little light on bugs me.

I'll be hanging around the coast mainly so the weather is milder.


The first hose is the only hose that actually sprung a leak, it was the one running from the EGR to the circulation pump.
I replaced them all preemptively because of that one breaking, the rubber was definitely getting old.
Hoses have not come off since the first few slipped off, I tightened them down good, but obviously that pressure had to go somewhere and its either out the top of my radiator cap, or this time it split my plastic tank at the seam.

Some of the few things I have changed are a starter and a radiator. My old radiator busted at the seam, so I thought it was just because it was old. I put a new one in and same thing happened.

I've got no plans to pull the head off, I know thats way beyond me.

I tried reaching out to the shop that did the work, but its just a generic receipt with a phone number, doesn't look official at all. To my surprise someone answered, but their english was pretty poor, it was hard enough for me to get him to understand that he had done the work already and not that I wanted work done.
Just to be clear im not suggesting you take a cross county road trip with a blown head gasket. Im just stating my personal experiences with t1n head gaskets failures. A 15-20 min daily drive to work and back on a blown headgasket could last for a long long time. Going over the rocky mountains.. maybe not so long. I will say I did have a client with an issue in flagstaff yesteday and he had a bad cap that was not releasing pressure. It was 110 outside driving through the desert up the grade to flagstaff and coolant started coming out of the coolant level sensor hole so definitely change a $12 radiator cap. If you want to know for sure whats going on buy a radiator pressure test kit. You dont need any of the additonal adapters for a sprinter
 

jrod5150

Well-known member
Thank you for correcting those costs.
I am going to try the glove test in just a moment here I'll post my results. After reading hkpierce's linked thread I see the engine should be warm because of the nature of some cracks only showing up at certain temps. Gaskets should show a leak right away, but a head crack or warp will only show up at certain temps. The advice I read was to warm it up with the cap off. To be clear I can drive the van with the cap off? That is the only way to really warm the van up, it will never reach temp at idle.

Your are correct that I did have a split on the plastic expansion tank on my radiator.

I guess it depends on how quickly that pressure is building, if I drive it like a grandma and boost slowly I may get some or no overflow from the cap.

If I drive it like I stole it hard and fast then that is when coolant shoots out of the seam on the tank. Its not a complete split in that the tank is now in two pieces, but coolant definitely comes out from the seam where the two pieces meet. This happened on the old radiator and the new one I put in.

I have my new OEM MB cap from Europarts-SD, admittedly I am a little hesitant to put it on as I feel like the pressure build up may be too much. This older cap is loose and provides some pressure relief.

Like I said I will try the glove test soon here and I will post my results.
I will give you a ring, I'd love to have you check it out since you've been around so many of these motors.


EDIT:

I just tried the glove test, but the engine was cold.
I revved it to about 2,500 RPM's several times for a few minutes, but the glove never filled.

I followed hkpierce's link and read that the engine should be warm. I will try it again with a warm engine. I read that a cracked/warped head will only show itself at certain temps when the metal is allowed to expand where as a HG will be noticeable pretty immediately.
The advice was to warm the engine up with the cap off. To be clear it is ok to drive my van with the radiator cap off? The van will never reach temp at idle.
Once the thermostat opens you can look down in the reservoir for a steady stream of bubbles.
 

Nautamaran

2004 140” HRC 2500 (Crewed)
Yes, you can drive without the cap to warm the engine, but you must then avoid extreme coolant temps.
Once the thermostat opens you should drive more gently...

-dave
 

PhillipisHappy

New member
Just to be clear im not suggesting you take a cross county road trip with a blown head gasket. Im just stating my personal experiences with t1n head gaskets failures. A 15-20 min daily drive to work and back on a blown headgasket could last for a long long time. Going over the rocky mountains.. maybe not so long. I will say I did have a client with an issue in flagstaff yesteday and he had a bad cap that was not releasing pressure. It was 110 outside driving through the desert up the grade to flagstaff and coolant started coming out of the coolant level sensor hole so definitely change a $12 radiator cap. If you want to know for sure whats going on buy a radiator pressure test kit. You dont need any of the additonal adapters for a sprinter
Yea I hear you, SF to LA is a pretty long trip. If I can do something like that I will cut my trip shorter but at least I will be able to get out.
I will put the new radiator cap on today, would be nice if it was just a $12 cap.

Thermostat opens at 192F correct? I will check for bubbles.
 

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