Repair to engine bay door

Topic: Repair to engine bay door (Read 1189 times) previous topic - next topic

Repair to engine bay door

August 06, 2019, 01:30:33 am

I have a crack in the fiberglass at the bottom of my engine bay door. See the attached. It appears the stringer failed and the flexing of the door when it is opened and closed has caused this crack to develop. I've explored several approaches to stabilizing the crack to buy me some time before I had Xtreme or some other fiberglass shop fix it properly.

At first, I assumed that the stringer had some wood inside or some other stiffening material. If that was the case, I was just going to bolt a piece of aluminum (1/4" x 1" x 18") flat on top of the stringer and through bolt it to a similar piece of aluminum on the outside of the door. But the stringer is hollow and I'm concerned that I might just end up crushing it and not stabilizing the crack.

Then I thought about using an aluminum channel (1/8" x 2" x 18") on the outside of the stringer and through bolting that as above. But the 2" channel is not wide enough to cover the stringer. There is a 3" channel available, but the sides are too deep. I have limited tools available.

My latest plan is to cut the end off the stringer and epoxy a piece of oak inside the stringer. Once that is cured, I could epoxy the end back on and cover about 18" of the stringer with a couple of layers of glass mat and epoxy resin. I realize the door is probably made of polyester fiberglass, but from what I can find, epoxy will provide a stronger and more flexible bond.

So what do you think? Potential problems? Other approaches? If I leave it alone I'm afraid the crack will continue to grow and become a bigger problem.

Re: Repair to engine bay door

Reply #1 – August 06, 2019, 01:52:11 am

George,

Fiberglassing over the full length of the rib, and an inch or two above/below, should do the job. Just make sure its clean, and then sand the surface for a good bond. 8-12 layers of glass matt and polyester resin should make it as strong, or stronger, than original.

Re: Repair to engine bay door

Reply #2 – August 06, 2019, 02:05:58 am

George,

Where you are, in a marine area, suspect anyone with a fiberglass boat repair place could easily and quickly permanently fix that.

Show that close-up picture to a couple of shops and get estimates.

It was probably stressed freeing up the frozen hinge/head banger.

Re: Repair to engine bay door

Reply #3 – August 06, 2019, 10:03:26 am

George, my idea of a good fix is as mentioned to you while here. Cut that top off the stringer and insert a piece of wood in the gap and fibreglass or epoxy the thing up, then a few layers of glass over top and down sides as well. First clamp a straight edge 2x4 across the outside of door to hold it in shape etc.
This can be done without removing the door
JohnH

Re: Repair to engine bay door

Reply #4 – August 06, 2019, 10:19:32 am

Just an observation, but the stick that's holding the engine cover up in picture #3 might cause a crack if it was used on the other side before. The engine cover is pretty much deadweight until lifted a bit higher that the struts come into play.

Re: Repair to engine bay door

Reply #5 – August 06, 2019, 10:58:37 am

T-Man... I have only put that stick there once, to take this pic. The crack was there when we bought the coach. I suspect that Brett is right and that the previous problem with the hinge caused undue stress on the door.

George

Re: Repair to engine bay door

Reply #6 – August 06, 2019, 11:12:04 am

George- another idea is to use 3M 5200 quick cure to fill and hold the crack. It is indestructible, holds well, water tight, remains flexible and is easy to use in odd areas. Just my thought, hope it helps.

Best of luck with your repair..........................

Re: Repair to engine bay door

Reply #7 – August 06, 2019, 02:27:26 pm

George..
I'll be watching your fix closely. We have the same , just not as big( not yet anyway).

Re: Repair to engine bay door

Reply #8 – August 06, 2019, 03:19:27 pm

I have repaired cracks like that before. First time I did it with epoxy and the my cousins told me epoxy doesn't hold to the mat and
he was right as it let go. So I got some fiber glass resin and some glass matting and it's good now. Make sure it's sanded as George said. You can make it a lot stronger than new.

Re: Repair to engine bay door

Reply #9 – August 07, 2019, 09:59:19 am

I haven't had to order from this company, but I did use fiberglass materials purchased from Lowes. This is the company from which I planned on purchasing bulk material. I was also planning to re-engineer the roof on our previous home, but I found another path and also avoided rebuilding the improperly installed resin bathtub and surround, well, the cracks were starting to hold hands as were my fiberglass reenforcements and the Lowes kits just weren't good enough. Professional materials may not guarantee professional results, but they're a start.

Fiberglass Cloth

Re: Repair to engine bay door

Reply #10 – August 16, 2019, 11:28:12 am

I'm finally done with the engine bay door repair. As described above, the door had about a 6" crack leading from the bottom of the door near the passenger-side edge of the notch for the receiver. This crack was present when we bought the coach and had not grown significantly in the last 8 months, but I wanted to prevent any further cracking. The stringer in that area had also cracked. When I opened up the stringer I found that it contained foam and thus bolting on some sort of physical support seemed inappropriate. So I cut off about 18" of the stringer and glued in a length of oak using West Systems G Flex thickened Epoxy (655). The doors are made of polyester fiberglass, but epoxy has more strength for repairs and this product seems to have superior adhesion to other resins in the West Systems line. Also, it is thick which is useful in working in this area and when cured it is more flexible than other epoxy resins.

This is a good Youtube video on the properties of polyester vs epoxy.

https://www.youtube.com/watch?v=Xnhz-OLZZa8

After gluing in the oak and letting it cure for 24 hours, I glassed it over using G Flex fortified Epoxy (650). This product also has excellent adhesion to almost anything but is less thick than the 655 product. I used 9 oz woven mat and applied one layer over the entire piece of oak with ~1" overlap and then the next day added another layer of the mat to each end and over the top of the receiver notch. The thickness of the mixed 650 resin does make wetting the fiberglass more of a challenge.

Of course, before doing any of the above, I had to straighten the bottom of the door. I used a piece of 2x4 with a 1"x1" steel reinforcing angle iron bolted to it. When clamped to the bottom of the door with large C clamps almost all of the bend caused by the crack was removed. I left this in place through the initial fiberglass application.

The last thing I plan to do is paint that area with some flat black paint, but that can wait. Thanks to all (especially John, Don, and Dave) for their suggestions on how to fix this crack. This was my first experience with fiberglass work. Thankfully, it is on the inside of the door and does not show!

Re: Repair to engine bay door

Reply #11 – August 16, 2019, 11:41:21 am

Nice job George! Looks like that will work.

see ya
ken

Re: Repair to engine bay door

Reply #12 – August 16, 2019, 12:40:58 pm

Sweet job, George!
jot

Re: Repair to engine bay door

Reply #13 – August 16, 2019, 01:05:45 pm

Nice job.

Re: Repair to engine bay door

Reply #14 – August 16, 2019, 03:38:13 pm

Looks good now George, knew you could do it all the time.
What is next on the agenda?
JohnH

Re: Repair to engine bay door

Reply #15 – August 17, 2019, 08:51:33 pm

Nice job George! If there's a will, there's a way!
John M.

Re: Repair to engine bay door

Reply #16 – August 17, 2019, 09:33:51 pm

Look like a professional job George!

Re: Repair to engine bay door

Reply #17 – August 18, 2019, 08:18:33 pm

Our rear engine access door now is lightweight and hinged up. It works very well. No more accidentally falling closed.

Re: Repair to engine bay door

Reply #18 – August 18, 2019, 10:26:12 pm

Quote from: Barry & Cindy – August 18, 2019, 08:18:33 pm

Our rear engine access door now is lightweight and hinged up. It works very well. No more accidentally falling closed.

Did you do away with the vents at the top of the door?

Foretravel Owners' Forum For owners and Fans of Foretravel Motorcoaches September 12, 2025 ...

Repair to engine bay door

August 06, 2019, 01:30:33 am

Re: Repair to engine bay door

Reply #1 – August 06, 2019, 01:52:11 am

Re: Repair to engine bay door

Reply #2 – August 06, 2019, 02:05:58 am

Re: Repair to engine bay door

Reply #3 – August 06, 2019, 10:03:26 am

Re: Repair to engine bay door

Reply #4 – August 06, 2019, 10:19:32 am

Re: Repair to engine bay door

Reply #5 – August 06, 2019, 10:58:37 am

Re: Repair to engine bay door

Reply #6 – August 06, 2019, 11:12:04 am

Re: Repair to engine bay door

Reply #7 – August 06, 2019, 02:27:26 pm

Re: Repair to engine bay door

Reply #8 – August 06, 2019, 03:19:27 pm

Re: Repair to engine bay door

Reply #9 – August 07, 2019, 09:59:19 am

Re: Repair to engine bay door

Reply #10 – August 16, 2019, 11:28:12 am

Re: Repair to engine bay door

Reply #11 – August 16, 2019, 11:41:21 am

Re: Repair to engine bay door

Reply #12 – August 16, 2019, 12:40:58 pm

Re: Repair to engine bay door

Reply #13 – August 16, 2019, 01:05:45 pm

Re: Repair to engine bay door

Reply #14 – August 16, 2019, 03:38:13 pm

Re: Repair to engine bay door

Reply #15 – August 17, 2019, 08:51:33 pm

Re: Repair to engine bay door

Reply #16 – August 17, 2019, 09:33:51 pm

Re: Repair to engine bay door

Reply #17 – August 18, 2019, 08:18:33 pm

Re: Repair to engine bay door

Reply #18 – August 18, 2019, 10:26:12 pm

Affiliate Notice