Overheating
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Jp mahoney
- Posts: 14
- Joined: Thu Jun 12, 14 12:20 pm
Overheating
Hi I’m having a few problems with overheating. Any suggestions. Does a cowl round the rad work. It’s a 440 standard engine. Recently rebuilt. Any suggestions really. Different coolant etc. Cheers
Re: Overheating
If it has been recently re-bored it possibly could get hotter than normal.
Shrouds are a very good idea.
Check your ignition timing too - ignore the old service manuals.
Shrouds are a very good idea.
Check your ignition timing too - ignore the old service manuals.
Pete Wiseman; Cambridge.
Mopar by the grace of God
Mopar by the grace of God
Re: Overheating
check the stat is in the correct way
check that that it is a 185 or 195 thermostat just bunging in a lower temp thermostat doesn't necessarily help
check there is one
check that your radiator cap seals. even new ones occasionally need the tabs bent over to account for wear in the filler flange edge.
it should be hard to do it up, and if it vents it should vent out of the tube on the side of the filler not out under the cap and all over the bonnet
too little ignition timing causes it to overheat in traffic, you end up with the flame front traveling into the exhaust headers making them red hot if it heats in traffic and cools again when on the move try a little more initial advance. but be sure to also check total advance at 3000+ you don't want it to pulling in 34+
way too lean can also cause it to get hot but i'd expect that to be accompanied by other symptoms and at a specific RPM or load
the fan being too far from the radiator causes more problems than not having a shroud. did you use the correct fan spacer for your motor/body type
if its a viscous fan, if it has been left for years lying on its face you can sometimes lose the viscous-nesss.
worst case you radiator is full of crap and the vanes on the water pump have eroded away .. if its a new ish pump the latter should not be an issue. takes years of cavitation (from running with no thermostat) and rust to do that.
do you have the right pulleys running the fan/pump too fast doesn't give the water a chance to cool in the radiator
do you have your heater plumbed in correctly
does your motor/pump have a bypass and have you mixed it up in some way with the heater plumbing.
last but not least is the pump the right one. i know you can get small block pumps that fit but are designed for modern engines and they are designed to run the other way i.e no good in an LA engine only good in a magnum/derivative.
don't know about big blocks at all.
Dave
check that that it is a 185 or 195 thermostat just bunging in a lower temp thermostat doesn't necessarily help
check there is one
check that your radiator cap seals. even new ones occasionally need the tabs bent over to account for wear in the filler flange edge.
it should be hard to do it up, and if it vents it should vent out of the tube on the side of the filler not out under the cap and all over the bonnet
too little ignition timing causes it to overheat in traffic, you end up with the flame front traveling into the exhaust headers making them red hot if it heats in traffic and cools again when on the move try a little more initial advance. but be sure to also check total advance at 3000+ you don't want it to pulling in 34+
way too lean can also cause it to get hot but i'd expect that to be accompanied by other symptoms and at a specific RPM or load
the fan being too far from the radiator causes more problems than not having a shroud. did you use the correct fan spacer for your motor/body type
if its a viscous fan, if it has been left for years lying on its face you can sometimes lose the viscous-nesss.
worst case you radiator is full of crap and the vanes on the water pump have eroded away .. if its a new ish pump the latter should not be an issue. takes years of cavitation (from running with no thermostat) and rust to do that.
do you have the right pulleys running the fan/pump too fast doesn't give the water a chance to cool in the radiator
do you have your heater plumbed in correctly
does your motor/pump have a bypass and have you mixed it up in some way with the heater plumbing.
last but not least is the pump the right one. i know you can get small block pumps that fit but are designed for modern engines and they are designed to run the other way i.e no good in an LA engine only good in a magnum/derivative.
don't know about big blocks at all.
Dave
The Greater Knapweed near the Mugwort by the Buckthorn tree is dying
Re: Overheating
Was the car always a big block ? A lot of small block cars left the factory with a smaller rad, 24" instead of 26" I think for a big block, so if it's a translplant you may need to upgrade the rad accordingly. The opening will be correspondingly smaller, my 66 was a 318 car now 440 has an aftermarket deep ali job which works fine.
Shrouds are good, especially if you are overheating at high speed, not so much if its at when at idle/stuck in traffic.
Shrouds are good, especially if you are overheating at high speed, not so much if its at when at idle/stuck in traffic.