Bonnet Won't Open!

Array

New member
I thought I would check my sprinters engine oil, brake fluid and power steering. But when I tried to open the bonnet it would not open. I first pulled the lever on the in side of the van but did not hear any click sound, so I went to the front and tried to open it but its stuck. What should I do? :idunno:
 

220629

Well-known member
... What should I do? :idunno:
If you are alone try pushing down on the hood bonnet few times to get it to spring against the latch. Push with your hands positioned backward down near the lip to reduce the chance of pushing in any hood bonnet sheetmetal. After doing that go to the hood bonnet release lever and try pulling it. Pulling against the upper part of the lever makes it harder to pull, but less likely to break the plastic handle.

If you have a helper have one person pull on the release lever while the other tries pushing down on the hood bonnet as described above in a bouncing action.

After (if?) you get the hood bonnet open squirt oil around on the latch parts that you see move when the lever is operated. Good luck. vic
 
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Array

New member
It Worked.

After I opened it I sprayed the latch parts with clear "Heavy Duty Silicone" and put the bonnet back down and tried opening it again but it didn't work. Should I use something else?
 

220629

Well-known member
It Worked.

After I opened it I sprayed the latch parts with clear "Heavy Duty Silicone" and put the bonnet back down and tried opening it again but it didn't work. Should I use something else?
Silicone would not be my first choice. The silicone residue will now have a tendency to keep any oil based lubricants from adhering and creeping in to do their job. It is not the end of the world though so don't worry too much.

Open the bonnet and inspect the pin which sticks down from the bonnet. There is a spring loaded piece on that needs to move up and down. Does it look rusty? Does it look bent?

The cable itself which the inside lever uses to connect and move the latch parts can also get sticky. Sorry I can't offer more. Have fun. vic
 

hkpierce

'02 140 Hi BlueBlk Pass
Open the bonnet and inspect the pin which sticks down from the bonnet. There is a spring loaded piece on that needs to move up and down. Does it look rusty? Does it look bent?

vic
My van came with that spring loaded mechanism mounted such that shaft hit the underside of the hood bonnet, thus restricting its movement. I had to grind it down to give it proper range of movement.
 

Boater

New member
It might be worth putting some light oil on the release cable itself and operate it a load of times to try and work the oil along it (like lubing a cycle brake or gear cable). I would probably use multipurpose grease on the actual latch mechanism.

Before going to too much trouble have an assistant pull the lever and see if the cable is opening the latch right up, cables can stretch over time and you might need to replace it. I have to admit mine needs just enough pull that the lever starts flexing, I'll probably get round to sorting it out just after the lever breaks :D:
 

mean_in_green

>2,000,000m in MB vans
Good thread, my release lever has always needed more effort than seems ok for the plastic handle to cope with. I think it's latch pin / catch alignment.

I wonder if it's worth mentioning for future reference about removing the grille before messing with the latch though - possibly gives more working room and options if your "two minute job" turns into something else!? I had to go to considerable lengths to get the bonnet open on my car once when the bonnet release cable broke...
 

cuffiesprinter

New member
If you are alone try pushing down on the hood bonnet few times to get it to spring against the latch. Push with your hands positioned backward down near the lip to reduce the chance of pushing in any hood bonnet sheetmetal. After doing that go to the hood bonnet release lever and try pulling it. Pulling against the upper part of the lever makes it harder to pull, but less likely to break the plastic handle.

If you have a helper have one person pull on the release lever while the other tries pushing down on the hood bonnet as described above in a bouncing action.

After (if?) you get the hood bonnet open squirt oil around on the latch parts that you see move when the lever is operated. Good luck. vic
Bumped into this 9-year old thread because I had the same problem (bonnet not opening in my Sprinter 2011).
The 1-person method didn't work for me, tried it in different ways, to no avail.
What worked for me was the 2-person method; one person keeping the lever pulled, not too hard, the other pushing the bonnet (and if required, pushing in a bouncing-fashion), that worked straight away.

Thanks!
 

JRossmn

New member
Thanks for this thread! I will add that in my case, having a second person push down didn't work, so then we timed it so he pulled up at the same time that I pulled the release lever, and that did it.
 

Lagom

Panic in Detroit
Silicone would not be my first choice. The silicone residue will now have a tendency to keep any oil based lubricants from adhering and creeping in to do their job. is not the end of the world though so don't worry too much.
I always assumed that hydrophobic oils would intermix without any problems. Am I mistaken?
 

owner

Oz '03 316CDI LWB ex-Ambo Patient Transport
In my recent case. I had to wait until the van cooled down, then the bonnet opened first pull on the lever as if nothing was ever wrong. I degreased it all of old gunky grease and used silicone spray and some graphite powder to lube the mechanism and cable as best I could. Works fine now.

The long version:
I had a minor coolant leak on one of the plastic fittings, about 1l every 250km. I did not have time to fix it because we were going on holiday in the van the next day. So I thought I'd be cunning and just stop and top it up every 250km on our 1200km round trip. You can see where this is going...

All was well stopping and topping up until I was about 200km from home returning on a hot day. The bonnet simply would not open. One person, two people, nada. The lever was very hard to pull, and it seemed like the sheath of the cable was deforming due to heat-soaking during a long trip in high ambient. I just nursed it home keeping a close eye on ECT and OIL temps. Made it home just fine and in the morning the bonnet opened perfectly.
 

tomd4s

Member
I've had mine not release a few times in the past when pulling the interior release. Being an electrician, I keep a piece of 12-2 romex wire behind the drivers seat. Wrap one end around the release lever and pull it back, wrap the other end around the steering wheel to hold it. Then go out and push or pull the hood and it pops. This will only work if your cable is good.
 

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