I am brand new to this forum and recently purchased a 68 Barracuda Notchback. It came with an LA360, which included a high rise single plane intake and double pumper Holley Carb. I swapped these out to be a little more street friendly. Now has an Edelbrock Performer intake (2176) and AVS2 650 carb (1906) and happy with the streetability so far. Biggest issue I have is the thermo housing/water neck leaking. Unfortunately, Edelbrock has provided zero help suggesting a recommended thermo housing and thermostat setup and actually told me that this is a known issue. I then contacted Jegs, Summit, etc. to get a recommendation and the consensus has been this set up based on similar past customer setups/issues. Billet Specialties Thermostat Housing (90820) and Mr Gasket Hi-Flow thermostat (4366). Issue is the thermo does not sit flush in housing so the set up does not work whatsoever. I suspect that the leak is due to the double bolt pattern on the intake. I doubled up a couple gaskets and used gasket sealer but the secondary bolt option on the intake sits right on the edge of the gasket and I suspect that is the reason for the leak. Any suggestions here would be a huge help before I pull all my hair out. I want to do this right and do not want to saturate this thing with sealer, silicone, etc.
Edelbrock Intake Issue
- Thread starter Mcfarlrm
- Start date
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Thermostat housing tend to warp and even more so when they’re made of aluminum. I doubt the intake surface has an issue. But check it & the housing anyway with a known straight and flat edge ruler. Unless you have a machinist straight edge.
OH!
Welcome aboard!
Where are you located?
Welcome aboard!
Where are you located?
Surfaces are straight on my current setup (swapped from last intake) and the suggested parts that Jegs and the other companies recommended are brand new. I was just curious to see if anyone on here has the same setup and has a reliable solution. Even took it down to my local guy who has been working on/restoring classics since 79 and he is also scratching his head trying to get the leak to seal mentioning he has never seen a double bolt pattern on an intake like this before.
Tampa area. You?
He’s never seen a double bolt pattern on a thermostat housing before? Did I read that right?
Just south of Melbourne
That intake, the Performer has had that double hole thermostat housing since the day it was produced and to read that the mechanic hasn’t ever seen one before and since ‘79 has me seeing a red flag approximately the size of Texas waving and slapping me in my face repeatedly like a cartoon.
So, are the un used bolt holes leaking? They holes go through to the Coolant underneath? If such was the case, a female allen hex plug with Teflon sealant paste would be used to seal it off.
How a mechanic since ‘79 can’t see this as a possibility and check for this is one of the most scariest things I’ve read here.
@ironbuilt or @Ironracer is in your area.
(Sorry fellas, I’m drawing a blank, I haven’t finished my coffee yet.)
So, are the un used bolt holes leaking? They holes go through to the Coolant underneath? If such was the case, a female allen hex plug with Teflon sealant paste would be used to seal it off.
How a mechanic since ‘79 can’t see this as a possibility and check for this is one of the most scariest things I’ve read here.
@ironbuilt or @Ironracer is in your area.
(Sorry fellas, I’m drawing a blank, I haven’t finished my coffee yet.)
Looks like that could be. (bolt holes into the coolant) I also noticed the thermostat housing the op is using appears to be o ring sealed and may not seal over a open bolt hole. Wow that intake has plenty of open ports that have to be plugged for our old engines and cars.
I haven’t laid eyes on a Performer intake in a very long time. I have no use for such an intake. I don’t know if those “Other” thermostat holes go through or not and if it’s not for the majority of intakes, it’s an auto check the second it comes OOTB.
I have never —- at least I don’t think so…. Used a “O” ring housing. The stock iron housings have not yet failed me.
I have never —- at least I don’t think so…. Used a “O” ring housing. The stock iron housings have not yet failed me.
QUINN FORBES
Greendemon
Those billet t stat housings have an “O” ring seal instead of the standard flat oe gasket. is the o ring intact/ok?
Do you have the right size t stat? There are 2 sizes of t stats for sb mopar. If you have the larger t stat it wouldn't allow the housing to sit flush inside the housing and therefore not flat on the intake causing a leak.
Cant see the unused bolt holes going through to the coolant passage but stranger things have happened.
Btw. I am pretty sure the double bolt holes are for a/c cars and allow you to turn the housing & upper rad hose away from the a/c crap for clearance.
I have the same intake in the garage and will double check if the bolt holes go through to a coolant passage.
Do you have the right size t stat? There are 2 sizes of t stats for sb mopar. If you have the larger t stat it wouldn't allow the housing to sit flush inside the housing and therefore not flat on the intake causing a leak.
Cant see the unused bolt holes going through to the coolant passage but stranger things have happened.
Btw. I am pretty sure the double bolt holes are for a/c cars and allow you to turn the housing & upper rad hose away from the a/c crap for clearance.
I have the same intake in the garage and will double check if the bolt holes go through to a coolant passage.
TrailBeast
AKA Mopars4us on Youtube
The 2176 has two sets of bolt holes and all are blind.
I never use a gasket, only red rtv and never an issue.
I have also always fired it up right after assembly without a problem.
Been doing it this way for decades.
@Mcfarlrm also.
MOPAROFFICIAL
Oogliboogli
Here's a little Mopar World secret for you ...
if the thermostat housing is Chrome.. it will not seal.
You'll have to surface all the chrome off the mating surface, 'scratch finish' and try again. Two times in my life I bought a chrome thermostat housing once when I first started out doing this...it leaked , I removed it. The other time about 15 years later when I forgot about the first time, it leaked and so I put an old rusted 1968 housing on after a wire wheeling...never leaked a drop.lol
Skip the fancy thermo housings and just clean up a stock one and paint it aluminum.
I know this is a Chevy part but I've been using it for years with no issue. The bolt pattern is very slightly off so it's not perfect but the bolts thread in fine for me. I used to struggle with thermostat sealing too. Tried a bunch of stuff. This solved it.
Summit Racing SUM-G3802 Summit Racing™ Chrome Water Necks | Summit Racing
I see that one isn't available anymore. This one might work...
Summit Racing SUM-G3803 Summit Racing™ Chrome Water Necks | Summit Racing
Summit Racing SUM-G3802 Summit Racing™ Chrome Water Necks | Summit Racing
I see that one isn't available anymore. This one might work...
Summit Racing SUM-G3803 Summit Racing™ Chrome Water Necks | Summit Racing
LMAO. Not available…
NoCar340
The Original Partstitute
Welcome aboard!
The dual bolt pattern allows the use of either the '77-older large thermostat, or the '78-newer small one (which is the same as a Chevy). Make sure your housing and thermostat match--the large stat will never seal in the small housing. Also, The Mr. Gasket thermostat should be avoided due to known quality issues--they have a high failure rate. Get the Stewart/EMP equivalent (expensive, and worth every penny) and use an OE thermostat housing that matches.
The dual bolt pattern allows the use of either the '77-older large thermostat, or the '78-newer small one (which is the same as a Chevy). Make sure your housing and thermostat match--the large stat will never seal in the small housing. Also, The Mr. Gasket thermostat should be avoided due to known quality issues--they have a high failure rate. Get the Stewart/EMP equivalent (expensive, and worth every penny) and use an OE thermostat housing that matches.
MOPAROFFICIAL
Oogliboogli
The older Mr Gasket thermostats used to be good. Mine's 20 years old and still works. Can't speak for the new ones.
NoCar340
The Original Partstitute
They're not all faulty, but with a high failure rate, why take the chance? The last time I tried one was in 2004, and it never opened. The car tried to overheat sitting in the driveway on first start with the new intake (also a 2176, on an '84 Fifth Avenue). I put the original thermostat back in it and never had a problem.
I only use Robertshaw-made, all-brass NOS Mopar thermostats now. They can still be found less expensively than the Stewart/EMP version, but either way is preferable to nickel-plated Mr. Gasket unit. Though the Mr. Gasket and Stewart parts are advertised as "high flow", they really flow at the rate around which Chrysler originally designed their cooling systems. Every Mopar V8 built through at least '79 had a "high flow" thermostat installed at the factory. The cheaper style of 'stat everyone sells now doesn't flow enough. Chrysler felt it was important enough to use this decal on motorhome air cleaners, with part numbers and a diagram showing what the thermostat should look like:
The verbiage is important: WILL cause overheating, not MAY.
Ironracer
Gearhead
Ys
Yessir, in Plant City/ Tampa Bay Area. Willing to help who I can, when I can. And right now, I have time.
Does the intake or the t stat housing have a machined pocket for the thermostat?
QUINN FORBES
Greendemon
My Performer 318/360 intake although crusty and old like me, does not have cooling passages in either sets of t stat housing bolt holes.
1st two photos show what toolmanmike is referring to with the machined pocked (stock t stat housing).
Not sure if the billet one has this provision.
Photos 3 & 4 show bottom of all t stat bolt holes cast closed off. I can not run my pick down through any of the 4 bolt holes.
I am still suspicious of the O ring system.
.
1st two photos show what toolmanmike is referring to with the machined pocked (stock t stat housing).
Not sure if the billet one has this provision.
Photos 3 & 4 show bottom of all t stat bolt holes cast closed off. I can not run my pick down through any of the 4 bolt holes.
I am still suspicious of the O ring system.
.
This maybe your solution. Ricks mopars on eBay.
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