The Promaster leaks from the cowl area and onto the engine compartment through several entry points. Moisture in the engine compartment during the warmer seasons, and ice build up during winter can damage different components. We already had to have our serpentine belt replaced because of ice build up, so this was high on our fix list.
Possible Entry Points:
Promaster’s leaky cowl is a known faulty design. Chrysler/Fiat refuse to acknowledge this issue and will not fix it under warranty. The dealer we talked to wouldn’t attempt to fix it even not under warranty. As owners, we are left to fend for ourselves, but we are getting pretty good at this fending-for-ourselves stuff!
We started with an attempt to seal what we thought was the issue, and fairly quickly realized that we’ll need to come up with a multi-targeted approach. There are multiple entry points, and every time we solved one area we would find another leak in another location. Below is a list of all of the areas that needed to be sealed by the end of this feat . The numbers correspond to the numbers in the photo below the list:
- the drainage holes and tubes on the side of the cowl are too small and clog easily, resulting in overflow into the engine compartment
- the seal around the drainage tubes leaks
- The seam between the two parts of the cowl leaks
- the large drainage hole drains properly, but the tube attached to it drains directly onto engine components and wires
- the seal around the wipers is not tight enough and allows water through
- the seal between the cowl and the windshield is open
- the gasket on the side of the cowls leaks
The process:
Fix 1
We started with what seemed to be the obvious — the drainage holes (#1) in the cowl and the seam between the 2 parts of the cowl (#3)
The small hole is in the middle of the white circle on the right side of the photo.
We drilled a larger hole next to it
and fitted it with a plastic fitting that we could attach a hose to
the hose drains to the wheel well and away from any components
This is a side view of the fitting
The seam between the 2 parts of the cowl (#3) had a gap that was easily open as shown in the photo below and we sealed it with black silicone.
This is what it looks like after we applied silicone
We really thought that this would fix the problem, but when we sprayed water on the van to check the seal, we discovered to our horror that there is a substantial waterfall gushing down underneath the rubber seal between the cowl and the windshield (#6). We also noticed a small leak from the seal around the wipers (#5). What???
Should We Give Up?
This was a good time to pay a visit to our local Chrysler dealer and inquire about options, so we got into the van and headed over. We already knew that Chrysler won’t fix this under warranty, but we thought that they may have some suggestions.
They did not.
The guy said that they won’t touch it because Chrysler just sends them the same part and this doesn’t fix the issue. The dealer doesn’t know how to fix it on their own so they can’t help us. They also say that they deal with numerous Promaster vans that are brought in because of damage caused by water in the engine compartment. Although they were sympathetic to our predicament, but no help whatsoever. The issue seems to be more serious than we thought and affects a large number of Promasters. Take a close look under the hood and check possible locations on your van if you own a promaster.
We see red flags around this issue. There is clearly a known issue that is the result of bad design/execution by Ducato/Fiat/ Chrysler. This issue results in failure of components in the Promaster van ranging from minor to major and there is no accountability from the company on this issue at all.
Next, we went to Speedy Glass to see if they could seal the glass in that location. Nope. They could have done something if the leak was into the cabin, but not if it’s leaking into the engine compartment.
We consulted a trusted mechanic, and a glass installer about some sealing options. They weren’t sure if glazing tape will adhere properly to the rubber seal of the cowl so we concluded, with their agreement, that sealing that area with silicone may the best possible solution.
Fix 2
On the first nice-weather day we tackled the rubber seal. First we protected the windshield and the cowl with painter’s tape, leaving a narrow gap for the silicone to be applied.
we covered the entire front and both sides above half way as the rubber seal seemed loose there as well..
We then lifted the rubber seal with a knife and started applying the silicone in the gap
smoothed and evened it out
pressed so that there is even distribution and to ensure that the gap is completely filled
remove the tape after a couple of minutes and before the silicone is dry
We tested to see if the area was waterproof by spraying the windshield with a hose and it seems to be water tight. A reminder to be careful when we clean the window so that we don’t snag the silicone.
The waterfall disappeared, despite the rainy weather, but we found a couple of entry points on both sides of the cowl.
Some people used successfully a silicone door sweep draft stopper. We haven’t tried it, but it seems to work.
Fix 3
Apparently the gasket under the small removable panels above the headlights area is bit too short (#7), leaving a small gap that allows the overflow to enter the engine compartment.
Our solution was to extend the gasket with silicone buildup.
This seemed to do the trick.
Fix 4
Next we need to seal around the wipers’ seal (#5) as there are some drops of water coming through. We will try to apply white grease that will repel moisture to fix this problem.
Locate the rod that connects the wiper,
apply the grease around the rod. This will not create a complete seal, but it is a good enough protection.
Fix 5
Last item is to extend the large drainage hose (#4) of the cowl so that it drains below the electrical cables. You can watch the effect after installation
Fix 6
Just to be on the safe side we also added foam gasket along the side of the hood.
The test:
Did it all work? Well, everything seems to hold for now. We are heading out for a couple of weeks soon and we’d like nice weather. Checking after rain storms and during winter after snowfall (when we are not travelling) is a good habit to develop. Rest assure that we will not rest until this van is watertight! It’s us against the machine at this point…
Please check under the hood of your van and try to identify potential issues and try to deal with them as best you can to prevent damage to your van. It is preventable once you know what to look for. It’s probably a good idea to carry with you a repair kit that includes a good waterproof tape for quick, temporary repairs.
We really think that this is a serious issue that needs more awareness. Feel free to share this post with other groups that you feel may benefit from this information. If we help save even one engine, we’ll be happy campers.
UPDATE: it’s been 6 months since we have applied the above fixes and we are happy to report that we are completely dry. We had several episodes of rain and snow and freezing temperatures and everything is holding up well. We recently bought a cover for the RV, which will be great for long-term storage.
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It must of been “Fiat” that designed the Cowel section . . .
Instead of silicone, perhaps a couple of tubes of polyurethane adhesive/sealer from a local auto glass shop along with a thicker (auto d-type) door molding would be a better bet. Harder to close, but it might provide better contact between the two surfaces.
Talk about waterfalls . . . I used about 18 tubes of the auto glass adhesive/sealer ($12.00 each) to seal every, single, rivet and interior glass and door joints on our vintage Airstream trailer.
Now it’s: Let it rain, let it rain, I can snore, I can snore . . . life of the road.
Thanks for this comprehensive article! I was finding water in the air cleaner intake and was concerned. I have started applying your findings. Thank you very much!
I hope it worked for you as well!
Thank you for sharing!
Thank you for taking the time to share this. My promaster looked like an ice waterfall down the passenger side of the engine a couple months ago. If I had known of the problem I wouldn’t have destroyed the ac belt trying to start it.
Oh, no! We now know better too…I hope you are able to take the measures to rectify the problem. Give us a shout if you have any questions!
Wish I knew you when I was still driving and had a car. Oh, well. Good information for other readers. Always good….
Also, luckily, not all cars suffer from this issue!
Excellent article! Now that more time has passed, do you have any improvements to your suggestions?
Thank you! We really had no issues since implementing these fixes. The only thing that we added was the RV cover to prevent debris accumulating on the van, especially if it’s parked for a long period on time under trees. I hope your leak is not too bad and that you can fix it quickly!
Much gratitude. I can fix anything, as long as there are instructions. After the fixes, I won’t be afraid to wash my van.
Haha, you are welcome! Feel free to shoot us a note if you have any questions!
Do you have a link for the fitting you used to replace the passenger-side tiny drain hole? The grommet on mine just disintegrated and the hose has nothing to connect to.
We didn’t use the original hole as is. We drilled a bigger hole and used this fitting as a connector: https://www.homedepot.ca/product/carlon-nonmetallic-liquidight-90-degree-1-2-in-fitting/1000117367
(This is in Home Depot Canada, but they probably have in the States if this is where you are. I can’t find it on Amazon.)
Just make sure to cut excess threaded piece above the lock nut and apply silicone around before tightening the nut. Good luck!
Thank you so much for taking the time to write such a helpful, detailed post. I’ve had several electrical failures (despite living in the desert SW), so I started the waterproofing process. It wasn’t clear what flange you used to hold the drain tubing in place, but the person at the hardware store suggested a nylon barb adapter instead.
So glad that this was helpful to you! Yes, this is what we used as well so it should work for you.
Thank you guys for a very helpful article! I have taken care of everything on my van now except for the white grease on the wiper seals. I’m not understanding how or where this should be applied. I bought a spray can of white lithium grease, so if you can give me an idea if this product will work and how to apply that would be great!
And finally, I am baffled by the air intake openings on top of the hood. Designed like this, how can you possibly keep water out?
Thanks!
Glad it helped, Todd! I added a couple of pictures and a bit of a better description under Fix #4. Let me know if it’s still not clear enough. The white lithium grease should be fine for this application. As to the air intake on the hood, the driver’s side is fake, and to our understanding, there is a drain hole at the bottom of the intake pipe to drain the water out. Who knows if it actually works… Let me know how it pans out for you!
Thank you for adding that info. Really appreciate it! I still have some work to do because I’ve still got water coming in at the top, but I think it’s getting better at least.
For the main cowl drain with the large black tube dropping down behind the engine, did you do anything to reroute that? Right now, mine dumps directly on top of my battery cables (red sheath), but not sure the best way to reroute.
Glad you are making progress. As to your question, yes, we extended the pipe to below all cables and electronics. We just extended the existing with a flex pipe we had. It’s the bigger pipe that you see in the video (the right handside).
Thanks again! I will take a crack at it…just one more round of fun. 🙂
Good luck 😂
Thanks for the info. What is the top three worst places that need to be fixed if I can not fix all the items you mentioned?
You should really try and assess your van and see where the leaks are coming from. You can then apply the fixes that address the situation that may be unique to your van. Our van’s worst offender was the windshield, so for us this would be the number one fix. The small drainage holes were also a top issue for our van. If you have leaks, try and do as many as you possibly can.
Thanks again for the tips. So far the silicone caulk has cut back on leaks. Since one of the stock drain tube flanges broke, I am in the process of installing larger drains below the windshield wiper mounts. From your photo it looks like you used vinyl tubing (which I have on hand). How has that held up? I’m trying to decide whether to order silicone tubing instead for added heat resistance. thanks
So glad this helped! As to the tubing, yes, it is vinyl, and yes, it held up very well since installed four years ago. If you are concerned about heat from the engine, it is nowhere near any significant heat. We hope this helps!
It does! Thanks so much for the speedy reply. Glad your drains are holding up.
Good luck with your repair!