Carb adjustment or too hot?

[bcbennett]

I live in west TX, where the summer temps routinely reach upper 90s or triple digits. When I drive my 74 TR6 in town, the temp gauge climbs with starts and stops, and pretty soon, the engine (recently rebuilt) coughs and sputters until I can drive a bit and get it cooled down.

Question: Is this normal behavior for a high-heat engine, or would adjusting the carbs somehow rectify it and allow the car to run well at that stage?

 

[Geo Hahn]

Not normal I would say. My TRs are regularly driven in 100+ temps but are the 4-cyl variety so I cannot directly comment.

Your problem may be help by the addition of a heat shield below the carbs. Such an item is now available from the usual sources foe the 4-cyl engine... perhaps something is also out there for the 6.

A marginal coil can also present problems when it gets really hot but in that case the problem will usually persist even when the stop & go is over and the engine returned to normal operating temps.

 

[RomanH]

I believe your engine is rebelling a bit from being too hot!
Adjusting the carbs won't do anything.
You may consider getting or making a fan shroud or getting a secondary electric fan to keep the air moving over the radiator while stopped at lights etc.
A fan shroud would also help in this area since the fan would only be allowed to draw air through the radiator instead of all around it as is the stock set up.
VB sells them look on page 62 of their newest catalog.

 

[RomanH]

Here is a link to a heat shield like the one George suggests.
https://cgi.ebay.com/ebaymotors/Triumph-T...1QQcmdZViewItem

 

[jerrybny]

I feel your pain. I just went thru the same thing. I would do the following:
First of all make sure your timing isn't retarded. This will definetly cause overheating.
Also I know you said it was recently rebuilt but if the timing and you have the shield in front of the radiator I would consider flushing it including removeing the block plug. Maybe some goop got loose in the cooling system. ALso the radiator could be plugged. You didn't say if you replaced it or had it recored. Good luck and this site is full of people waiting to help you solve your problem. /ubbthreads/images/graemlins/cheers.gif