The Stovebolt Site Forums The Parking Lot Big Bolts Just say no to Crack

Well, it looks like my truck season is over. I knew I had a questionable donut gasket on my cabover so I removed it and sure enough it was shot. I order and installed a new one and found out pretty quickly that I have a much bigger problem...
The intake manifold above the carburetor is badly cracked.
This old picture pre-restoration shows the location. It is on the front part of this "square area".
http://i1366.photobucket.com/albums/r780/Marlowcoal/crack%20before%20crack_zpswy8ukgch.jpg
It is very tight in there but here's a picture showing the crack
http://i1366.photobucket.com/albums/r780/Marlowcoal/crack_zpspjqmzwva.png
No doubt it will need to be replaced. I am hoping all those folks out there that have taken there COE's and put them on modern chassis haven't just scrapped all the original stuff.
Pretty bummed out knowing that parts wont be easy to find and that I wont be able to cruise for a while.
I wonder what would have caused a crack like that.

Don't scrap the damaged manifold- - - -with a little cleanup and some careful pre- and post-heating a good welder can repair it. There's even nickel-alloy wire available for a MIG welder for such repairs. That's the area of the manifold that carries the exhaust gas from the heat riser, so there shouldn't be a vacuum leak from it, just exhaust.
Jerry

ditto Jerry's post.

Wow, I wouldn't have thought for a second that that could be repaired. I will try and get it removed this week. Hopefully it isn't worse that it looks now. When I get it off I will post a better picture.
Thanks guys.

Bill, there is a COE at a boneyard that I frequently visit that I am pretty sure still has both the exhaust and intake manifold still on the engine. Not sure what year because the front clip is missing, but I can check it out for you if you would like. I'll probably be stopping by there tomorrow or Wednesday. I'm pretty sure that the engine is a 235. The guys let me pull my own parts, so if it is what you want, I can pull it and ship it to you. If you PM me your phone number, I can call you from the yard and/or text pictures.

Let me know,

Matt

Matt, that sounds great. Not sure if the advance design era COE's had the exact same set up as the art deco's. That would be my only concern. I will jump over and send you a PM now.
Thanks a lot.

41-49 COE manifold the same. Takes Carter model 517 updraft carb. 50-54 COE manifold the same. 50-53 takes Carter model 871 updraft carb., 54/55.1 takes Carter model 2075 updraft carb.

Wow: When you said a crack,you meant it! I've had issues with my newer 235 sucking oil out of the air cleaner. I guess to much vacuum. The newer motors with the original manifolds and sheet metal can cause issues. Good luck getting it back on the road. Too hot to drive mine much ,it's hot down here!

Make sure if it does get welded, to bolt it to a dummy piece of steel(.5" would be great) or a head if possible to eliminate any possible distortion, and to keep the whole assembly together, if possible.

Ed

HI
You probably can get it welded or make a new one
I bought a fenton and prefabricated it to run a downdraft.
you can fabricate to take the updraft.
see the one attached
chris

https://photos.google.com/share/AF1...Y09Tdll5N0NGUjJ1QjVwQmh0M1NmMVMxMkFzcVdB

Bill, Ship it to me and I will get it welded up. Address is listed below.

Thanks,

I just got a call from Matt right from the bone yard! Unfortunately, the truck he was looking at was a GMC, so wrong manifold. Matt, can't thank you enough for looking for me and offering to retrieve and ship the parts.
Got to love this site!
Randy, I haven't pulled the manifold yet but when I do I will post a picture to be sure it is doable. Thank you as well for the offer to help. I really appreciate it.
Billy

Its great to see fellow Stovebolters helping a guy resolve his crack problem, so cool. Billy I hope you are back on the road real soon.

I think I am going to give up my crack problem.....Because, I struck gold right in my own neighborhood!
http://i1366.photobucket.com/albums/r780/Marlowcoal/Mobile%20Uploads/image_zpsxjyz5vci.jpeg
I remembered talking to a guy at our local cruise in that told me he was building a '46 COE crew cab custom job a couple of years ago. He told me he had a late model one ton dually chassis that he was going to set the cab on. I still had his number in my phone an called him Tuesday morning to see if he still had the old chassis and engine. I told him I was looking for the manifolds but he couldn't remember if they were there. He called back later that day and said everything was there and mine for the taking! I still wasn't sure if I was out of the woods because I was told that there were a couple different COE manifolds in those years. A friend in Canada has several Art Deco cab overs with at least two different set-ups.
So anyway, I got to the house yesterday afternoon, less than 5 miles from my place and there was the engine, laying on its side (manifolds up!) just waiting for me. Checked the casting numbers and they were the same! I think it took me all of about 5 minutes to remove them and put them in my truck. I called George (the owner) and told him I had some money for him and he wanted nothing of it. He said "I don't work like that. I told you could have the parts so they are yours". I will figure out a way to repay him for sure.
http://i1366.photobucket.com/albums/r780/Marlowcoal/Mobile%20Uploads/image_zpsqed6ucsi.jpeg
http://i1366.photobucket.com/albums/r780/Marlowcoal/Mobile%20Uploads/image_zpsxuepndjz.jpeg
Last night I removed what was left of the carb and exhaust etc and got it cleaned up in the sand blaster. I don't see any cracks whatsoever and looks to be in pretty good shape. Need to paint it up and find some new gaskets and maybe even get the truck back on the road soon.
Its been a long time since I put the engine together so would the exhaust/intake manifold gaskets be the same for the coe engine as a conventional setup?
So for now it feels like I hit the lottery.
Hopefully my nasty crack problem is behind me!

Quite the lucky guy!

Manifold gaskets to head are the same.
Looks like the manifold to manifold gasket is special on the COE.

Grigg

Yep, even a blind squirrel finds a nut once in a while.
I am going to take a chance and not split the manifolds. I have heard horror stories about trying to separate them and breaking or cracking them.
I will keep my fingers crossed.

Sounds like a plan.

Have them flattened if necessary.

You mentioned sandblasting them. I am really hesitant and pretty much avoid blasting any internal engine part, the interior of the intake manifold qualifies.
I worked on a very fancy car from the 30's where the previous shop had bead blasted the entire engine inside and out during a rebuild. They seemed to have done a pretty good job overall and I have no doubt that they washed and cleaned it all quite well before assembly. My work involved removing both heads and once removed there were lots of little piles of glass beads in the nooks and crannies, brought by the oil and settled out where it couldn't drain back.
From this (and other's similar accounts) I've learned that no matter how hard you try it is unlikely you can wash and clean and remove blasting grit entirely. It may be partly embedded in the metal surface only to work loose later.
So I don't blast anything where remaining grit could cause harm to the engine.

If there is any gunk or varnish or what have you inside the intake manifold and even if you didn't blast inside it is likely that by blasting outside some grit has gotten trapped inside. Just do what you can to wash and scrub it out.

Grigg

glad you found one local, that is always great! Also nice to find someone to swap "junk" with! He may need something you have an extra of at some point

Congratulations Bill. I agree with Grigg. I wouldn't bead blast it. Just clean it up, & paint it.

Don't you love when things come together like that once in a while? You will be cruising in no time.

Visit your back woods dealer for your crack fix billy? First rule of recovery is to identify your weakness and the kick it in the arse. Sounds like a few days in rehab and you should clean up nicely and be a productive member of our society again.

Thank you Dr Bone!

You should go buy a lottery ticket. Thats really lucky to have found that rare of piece 5 miles from your house!

I did buy a ticket but no luck there. My luck was used up finding that manifold!

Just curious, did the donor motor have gaskets on the manifolds when you removed them?

Mike B

Congratulations, Mike

If your COE's manifold is scarce, feel sorrier for those of us with a cracked GMC 270 COE exhaust manifold.

A "good" welder considered welding it a few different ways. He finally resorted to spray-welding. He machined all mating surfaced after it cooled downed.

The "ping" from the new crack in another location when we attached the manifold caused a few foul words/expressions.

Luckily, the new cracks do not create an exhaust leak.

Mike, it did have gaskets. Why?

Congrats, Billy. See??? Karma *does* work in favor of good guys.

You deserved a good deal and I'm glad one found you.

Bravo Zulu.

The reason I asked was some exhaust manifolds don't use gaskets to allow the manifold to heat and cool at the same rate as the block. I was curious if the inline 6's were that way and that engine looked "untouched".

My 322 V8 doesn't have gaskets and I'm told if used the manifolds will crack. The bad thing for the inexperenced builder is that the gasket kits provide then even though they where never installed with them from the factory...

Mike B

Wow, I had no idea. Definitely had gaskets.
I ran a straight edge across the ports and it is as good as I could ask.
I just need to find new gaskets, hopefully before this weekend...

Billy,

I had to make my gaskets from NAPA FPG2499 exhaust-manifold sheet-material. (GMC, not Chevrolet)

http://www.1954advance-design.com/Web%20images/270-manifolds-repaired_3.jpg

Won't the gasket Billy needs, manifold gasket to head, be same as other 235s? Not hard to get.

Grigg,

You might be correct.

However, the GMC COE 270 exhaust manifold gasket/gaskets are different from the gasket/gaskets used on the standard GMC 270 exhaust manifold: the gasket/gaskets between the "heater box" between the intake manifold and the exhaust-manifold

Chevrolet Truck: Section 3.272 Gasket Intake to Exhaust Manifold : 39-54 DUBL DUTY and COE vs the gasket for other trucks

All Right: What a find!! When I put my truck together 8 years ago or so. I didn't split my manifolds, all that rust can cause issues. I had to double gasket one of them to make the even. Then used plenty of high temp.sealant. Also torqued all the manifold bolts once the engine got up to temp. I've never had a problem with that part since.

Report:New/used manifold installed and the truck already runs better. In hindsight, I think that crack may have been occurring for a while. In a perfect world, it only gets driven on the weekends during the spring summer and fall so I may have just not noticed the lacking in performance (due to the slowly progressing crack), especially when the vehicle will only go 43 mph! That and I knew I had a donut gasket going bad.
My truck would have originally had a 216 in it. When I bought it, it had a 1954 235 in it. I compared the old and new manifolds prior to installed the new one and they were, of course (same casting # sooo...) exactly the same. When we first attempted to put the manifold on, we could not get the second to last and last bolts in no matter if we were working from front to back or vice versa. We removed it and compared again only to discover a small notch ground out of the inside ear on the last exhaust flanges on each end. Looked like a "farm" modification when the engine was changed, so we did the same with a die grinder
http://s160.photobucket.com/user/st...16D7_zpsrxssgxut.jpg.html?sort=2&o=7

Worked like a champ. Had it back in and back together in new time with the help of some ODSS Brothers (thank you guys!).
Getting it back on the road has motivated me to fix a few other things that have needed attention. Oh and we found out my vacuum advance is no longer working so Chris Sweet assures me that the COE will be doing wheel stands when it is replaced!
I'm just glad its running decent again.

I was taking a closer look at the cracked manifold Sunday night. I hardly touched the large cracked section and it fell right off. I didn't take a picture of it but am still wondering if there is any chance it is repairable for a spare. I definitely would like to have an extra one sitting in my parts cabinet.

I had to grind my original manifold so it would bolt up to a newer 235. There must of been small center to center change on the hole pattern some where in those years. The bigger trucks all came with 235's, just Babbitt ones. Congrats on getting back on the road! I'm still waiting for it to cool down here to get mine out much,our summer is like your winter.