sb 360 - one head is hotter than other - What may be happening?

[cezagonel]

Hi,

I'm a Brazilian guy. I have one brazilian Charger R/T 1976, like a American Dart 1969.
Well, this Charger, originally was 318, the only engine made in brazil.
I make one 360, with a scat crank and proper pistons. This engine was assembly with Eddy heads, performer rpm intake, headmann headers, crower 271/284 hid. cam. The compression ratio is 10:1.
In last week, when i startup the first time, i observe that head of passager side heat early than driver side, and the header, mainly cylinder 6 and 8, got almost red.
Today i disassembled the heads, and i didn't find anything wrong with the heads or gaskets.

Well, may you can help me! What you think about it?

Ps.: I measured the exhaust header temp with one IR thermometer. The driver side temp was around 520ºF and the passager side, 4, 6 and 8 was around 840ºF and the cylinder 2 was 630 ºF.

Thank you for your attention.

I like a lot your forum!

Carlos

 

[Robbie2734]

It's running really lean on the passengers side, look for a intake gasket leak there. Probably at the rear of the intake gasket. I don't think it's the carb, but it might be the carb gasket???

 

[jimjimjimmy]

its a lean condition for sure

 

[Hersbird]

I don't know about your problem but I would love to see your car. It sounds awesome. I was impressed when visiting Australia in the early 90s at the Chrysler stuff from there. Brazil seems like a great place to live as well although the cities seem a bit crowded for my taste. Did you convert it to run on sugar ethanol?

Oh I had to google it. If it's like this one the I say very cool! I hope you stick around as this is the best Mopar A body website in the world.

 

[robert 68 cuda]

intake problem or valves are out of wack and whats your timing set at ???

 

[OldmanRick]

Welcome Carlos.
When you say you started for the first time, did you mean the very first time, as on the break in first time? Reason i'm asking is, you can get some crazy temps on the break in start up and i'm just wondering how much run time you had when you took those temperatures? Also, what were you coolant temps?

 

[OwdKasd]

Some Carbs come with no plug in the back. Like My edelbrock 1406. The plug was in the package and I didn't realize it. It was a huge vacuum leak. Just a thought...
Good luck with it. I'm sure you'll find the Vacuum leak if that's what it is.

 

[mopar410]

did you have the dowel pins on the block ..you might have put the head gasket on backwards.There is a water outlet that is blocked if put on wrong,but oddly when put on right it still bloacks an outlet so that part bothers me.

 

[None2Slow]

If the intake is changed, then the dowel pins might still be in holding the intake up just a bit. This would cause a leak at the intake.

 

[cezagonel]

It's running really lean on the passengers side, look for a intake gasket leak there. Probably at the rear of the intake gasket. I don't think it's the carb, but it might be the carb gasket???

I don't think it's the carb, soo. I use a holley dp 650, and change for a holley dominator 750 to test, nothing change.

Probably tomorrw i will get news, because yestarday i change the heads of the side. I will reassembly the intake, may be if there are some problem in the intake gasket it will get solve.

Thank you,

Carlos

 

[cezagonel]

Welcome Carlos.
When you say you started for the first time, did you mean the very first time, as on the break in first time? Reason i'm asking is, you can get some crazy temps on the break in start up and i'm just wondering how much run time you had when you took those temperatures? Also, what were you coolant temps?

Yes, was the break in. The engine run about 20 minutes. After that i run more two or tree times about 5 minutes. Everytime the headers of the cylinders 6 and 8 heated early.

The coolant temperature was good, like 180ºF. But in this time was without thermostatic valve, is it a problem?

Thank you,

Carlos

 

[cezagonel]

did you have the dowel pins on the block ..you might have put the head gasket on backwards.There is a water outlet that is blocked if put on wrong,but oddly when put on right it still bloacks an outlet so that part bothers me.

The head gaskets was right. I removed the heads yesterday and the gaskets were correctly installed.

Thank you,

Carlos

 

[cezagonel]

What is the expected temp in the exhaust headers?

Thank you,

Carlos

 

[OldmanRick]

Yes, was the break in. The engine run about 20 minutes. After that i run more two or tree times about 5 minutes. Everytime the headers of the cylinders 6 and 8 heated early.

The coolant temperature was good, like 180ºF. But in this time was without thermostatic valve, is it a problem?

Thank you,

Carlos

Themostat out for what your doing right now wont be a problem, but once you get this straightened out and get on the road you will need to use one.

I would try advancing your timing 4 to 6 degrees for "test purposes" and see if the temps. even out. Could just be retarded timing and a little lean and because of intake tract inconsistancies shows up in those cylinders first.

 

[cezagonel]

Well,


After i disassembly and assembly the heads and intake, nothing change.
I tried change the water pump, put a mopar hi-volume pump and surprise, the temperature was much better.
I think there wasn't enough water for the aluminum heads.

Thank everybody for the help.

Carlos

 

[spinman_1949]

Carlos,

So you now have even temps in all cylinders? Seems odd that more water flow would straighten out this issue. Unless of course the flow on the cylinders running hot was poor to start with. Keep an eye on it.

 

[OwdKasd]

Glad to hear she's running Cool. Enjoy the Mopar.