The Stovebolt Site Forums The Shop Area Engine Shop 1946 235 manifold gaskets

Hi everyone. Seems that every couple of years I'm re-installing the manifold gaskets on my 46. Its always a different spot that gives up first, but something always gives up. The manifolds appear to be flat when properly aligned and assembled, but I'm just laying them on a flat surface, not using something they would have down at the machine shop...although I vaguely remember having them checked out when I had the head gone through. Anyhow, while looking around the web the other day, i stumbled on Re**lex gaskets (don't want to be an advert). I haven't seen anyone mention them on here, but I went ahead and picked up a set just to try them out.

First off, they are expensive, If I don't get about 8 to 10 years on them I'm out whatever that pro-rates to compared to a 2 year cycle on the normal style gaskets. They are thicker than your usual exhaust gasket and have no metal, and are crushable to about half thickness. They offered the head to manifold gasket as one precut assembly, I did like this as it was slightly easier to keep everything lined up while sliding on the manifolds and getting the alignment rings started than the standard 3 part gasket set. They did not offer a pre-cut gasket to go between the intake and exhaust, so I ordered a small blank of the material and cut my own. The material is somewhat fragile especially to bending, but it is also fairly easy to cut with a utility knife. Everything went together as expected, and in less than 4 hours I had everything pulled, cleaned, cut, assembled, aligned, torqued, and re-assembled.

Truck fired up quickly, and no vacuum or exhaust leaks. Well ok, there was a real small one at the donut on the downpipe, its the same old regular material... Shutdown and loosened, reseated and re-torqued the downpipe, and restarted. No leaks. So far, I have about 15 minutes of run time on them, tomorrow I hope to venture into town for a real test. I'll let everyone know if they hold up or are best used to lubricate legless reptiles.

Check my gallery below for some photos of the install.

Well, the test drive into town was uneventful as expected. I did re-torque the down pipe donut after getting back and things cooled. It had loosened a little. The new gasket instructions say that re-torquing is not only not needed but can hurt the gaskets. Being curious I carefully put some pressure on all of the bolts, without moving them. None were loose and are probably still at their install torque. The gasket has no sign of heat damage or leaks, but does have a separation occurring at the bolt between the front exhaust and intake flanges, and identically between the rear exhaust and intake flanges. Probably from the elongation that occurs with the temperature changes. Here's hoping I can report back in a couple of years saying it's all still working.

for some reason the picture won't show up on my computer. But I think I know the stuff you are talking about, what we used was kind of pink standard looking gasket material on the outside, with black graphite looking stuff in the middle. If it is the same stuff it will last a good long time.

2ton46, just picked up a set of their exhaust gaskets for a 235, not installed as yet. Learned of these from my muffler shop buddy, he's been using them for a while and loves the product. They go on dry so no mess and I like that they are one long piece. I got mine from Summit Racing which is a bit cheaper in price, have Chev and GMC. I'll attach a link to a video on them. Best of luck
http://catalog.remflex.com/

Was poking around under the hood this afternoon and while I was looking everything over I realized that it's been 4 months and a bit over 800 miles since I installed the manifold gaskets. I'm happy to report they look exactly the same as they did the day I installed them. No discoloring, no leaking. Excepting a little dust on the visible surfaces nothing looks at all different. The two separations near the bolts mentioned in my posts above are apparently stable, as they don't seem to be any different than after the initial drive cycle either. I think this gasket material is going to work out ok. I'll try to remember to update this again around the 1 year mark or so...

great news, you sure have a nice truck,
keep those cows mooing..

regards,
Fred

Well, its been just about a year, will be in a couple of weeks. Happy to report that the gaskets are still there, not leaking, and look just like they did when I installed them. Well, maybe a little surface dust, but no leaks and no sign of impending failures after a couple of thousand miles.

I can report back that these gaskets are still working just as they did two years ago. No signs of leaking or deterioration and those separations mentioned in prior posts are stable.

They are great, however, they don't make them for all, not GMC 503, ordered raw mat'l from them, could not make good gaskets from scratch.

Don't forget, we need to leave the bolts between manifolds loose until they are both tight to the head.

Ed

I have been using Rimflex gaskets for some time now on my motors. I really like the. They seal when all others would not. Couple of dollars more expensive but worth it in my view.

Thanks for the product report, it is good that you have taken the time to develop and share your review.

It has been almost another year and I can report that they are still sealing the manifolds to the head like they did on the first day - also the between the intake and exhaust piece is still in there too that I cut from some of the material.