Crack in Resin on Thermoquad carb - 440

[freestyledude]

Chasing down a vacuum leak with carb cleaner I found that the idle would surge spraying the back of the carb (not into the intake)
Pulled the carb off and found this small crack when I took it apart. (P.S. Watch for the two hidden screws below the choke plate before you start beating on it)

[freestyledude]

it doesn't look like it goes all the way through, but the gasket looked pretty good, it certainly wasn't torn up at all.
I'm at a loss, I can't find that plastic piece anywhere online and I'm guessing my local parts stores won't either. Is there any way to patch this up to prevent a leak? I definitely don't have the money right now for a whole new carb.

[PEntertainment]

I bet the right epoxy resin would work. From JB weld to plastic epoxy, something should stick to that and not be affected by gas. But what is it? Maybe someone reading this post will know. Maybe you'll have to do the research yourself - other websites? call manufacturers? or even buy different products and try them out. Good luck, I know most stuff is affected by gasoline. I've used plasitc super glue and plastic epoxy with good results but you have the gas factor. I can't see with the picture but if it is a hairline crack the super glue might work. I'm no expert though, just throwing out ideas.

[freestyledude]

I think you're onto something with the epoxy, I bet there's a product out there that is resistant to gasoline.

[vincewarde]

Yep, I have seen product at the auto parts store that specifically said they were OK in gasoline.

[freestyledude]

Perfect! I think that'll make life easier. I have a suspicion that the leak was from a lack of gaskets on either side of the rubber spacer on the manifold, but I thought I'd rip the carb apart to make sure. Might as well seal up this crack and give it a whirl!

It would be awfully nice to get this beast on the road soon! It was definitely a stressful hour-long drive with this rig running as poorly as it was.

[jkilbert]

If its the plastic carb body that's cracked, my suggestion is to get another carb. I had the same thing happen to mine and tried epoxy to fix it without luck. A friend of mine is a Mopar guru and said the plastic body thermoquads are essentially throwaway carbs. I switched to a 650cfm Edelbrock and am enjoying it ease of maintinence.

[DELTA912]

When in doubt REPLACE IT. There's a guy near me that has carbs for 318, 413, 440, and 360 engines. He does shipping and gets the carbs rebuilt.

He sends in 3-6 at a time and gets maybe 1-2 that will work and are already broken in. I'm going to see him today some time, so I'll ask what the going rate is for a carb that's ready to go. He might want yours for parts.

[DaveVA78Chieftain]

Price is high: http://www.carburetion.com/Carter4TQ.htm

I have no clue about $ but he says the epoxy works for this application: http://www.ihpartsamerica.com/forums/carb-tech/1390-carter-thermoquad-spreadbore-stuff-2.html#post24423

Dave

[freestyledude]

Ended up being out of epoxy and putting the carb back together with new gaskets. Seems to work fine so far, I'll keep everyone updated.

[PEntertainment]

Sounds like a good product that should be filed in the "hard to find expert recommended products" section. Text and links from the website in case that site goes down:

"That would be..."Epon" Epoxy MS 907.
Sourced from Miller-Stephenson.
Their website is kinda scruud up, but the info is there if ya search:
Stuff has to be ordered direct as far as I can tell, I haven't tried to buy any yet...but I'll need more soon."

Miller Stephenson website:

http://www.miller-stephenson.com

[DaveVA78Chieftain]

I will look into adding a link to it this evening when I get home from work. - Dave

[cosmic]

I have read several people have had good luck with jb weld and the guy in the article says his failed. not sure how well it was clean.
I once crushed my motorbike tank. I drilled a 3/16th hole and pulled it out and epoxy glued it and it held for 7 years.
my mechanic buddy is trying a epoxy for rads. on the area that gets sealed where the jets are. I  will let it sit for a few days with e10 gas in it. Ill let ya know if it works.

[DaveVA78Chieftain]

I am interested how it works out.  Good luck - Dave

[cosmic]

the product I used is called. plastic tank and radiator repair kit. Made by Versa Chem (Devcon) it is a 2 part epoxy. we left it in gas. (e10) for 3 days to see if it would break down. then assembled the carb. Seems to be working great. and holy shoot that 440 has just been woke up from a long coma. The thing goes like a bat outa hell. LOVE IT.

[Oz]

One of our most overlooked yet excellent resources is the book, "Rx for RV Performance & Mileage"

It details this same repair, using the same method... along with many other, common problems and easy, inexpensive repairs found on these old model RVs!  It covers Dodge, Chevy, Ford...

It's an excellent read for everyone, loaded with extremely valuable information.
If there's any book beside the factory shop manuals you should have in your library... it's this one!

http://www.classicwinnebagos.com/forum/index.php?action=store;sa=view;id=184

[DaveVA78Chieftain]

At least that product is advertized  to be chemical solvent resistance to gasoline, diesel and kerosene.  As long as it adheres to the plstic then hopefully you will be good to go.

Dave

[cosmic]

Note to all.
On my first long trip. my epoxy failed. i'm running rich again. 5.3 miles to a gallon. must try another epoxy product.
spoke to my mechanic friend and we are going to try the marine epoxy next.
I really thought the rad epoxy was going to work. it lasted for all the little jonts here and there, but when I got the first hour on the hwy. that was it.
I'll keep ya all posted so you wont have to go through what I did, and you can get it right the first time.

[cosmic]

UPDATE
After tons of reading I found a product that will hold up to the e10 gas. the company name is miller Stevenson and the product is called ms 907. I spoke with the lady at the order desk and found out you need to be a business in order to order from them, and the minimum order is 4 units. I told here I only need like a gram or two to seal up the bowl in my carb. she directed me to the technical support division who sent me a free sample of the product. that's right FREE, and even payed the shipping and everything. This is the only product that will hold up to the alcohol.

In the USA at jegs you can buy this stuff under a different name. Murphy's miracle epoxy.$19.99 This is the same ms 907. Sorry they cant ship it internationally do to laws.

So if your in Canada like me find someone with a business and call miller Stevenson  ask for tech. support and beg for as free sample. this  stuff is the bomb. this took me a lot of time and effort to figure this out. Please don't use jb weld unless you only ever use premium fuel. It will not hold up to e10 gas.

For those of you who are running reg. fuel you are running rich. if your exhaust is black you plugs are chocky black you need to re epoxy your bowl. there is a huge I mean huge difference is the acceleration of the rig because I am no longer running rich. (LISTEN UP) you will not regret the advice I am giving you.

yes I know this is posted above by another. he just never tested it. I did and it works.

[Dr. Righteous]

I'm reading a lot of doom and gloom in this thread concerning TQs. 

Walker has a full parts inventory (yes even pholic bowls assy) as well as kits.

http://www.walkerproducts.com/products/carburetor-repair-kits/

https://buy.walkerproducts.com/carburetor/components/


The large bore body (1 1/2") is $100.58
The small bore (1 3/8") is $88.79

Also O'rileys Auto Parts carried Walker products.   
OH, and by the way; if someone claims they are a "mopar guru" and says a TQ is junk; find yourself another MoPar expert. 

[jkilbert]

He didn't say the thermoquad is junk, just the plastic bodied ones. BTW he's running a pair on a Hemi Coronet  that runs low 10's In the 1/4. No blower or bottle on it.

[GONMAD]

Hey Guy's Just a note... I have been using Marine grade 5200 Sealer inside my HYCO units for a while with NO failures as yet. It's white & easy to tell if it doesn't work. Also if you have to, try the new 750 DEMON Phenolic Street Demon It's a modified design & we have had GOOD results with the 625 & I suspect the 750 would be just the ticket. I must admit the 625 limits the WOT performance but not an RV witch only runs up to 3500 at the most but try the 5200 it's tough stuff. C YA! GONMAD