Coolant temp grows quick
Thread Starter
Intermediate
Joined: Aug 2008
Posts: 48
Likes: 1
Coolant temp grows quick
Ok guys I need some help here,
the temperature grows quick from 150° to 230 and even higher (at idle and running) I notice that coolant droops to coolant reservoir (this coolant is cold). I disconnected the radiator inlet hose and saw that the coolant flow is intermitent....sometimes it flows, sometimes not
I pulled out the water pump, and didn't notice any impeller problem. I have a brand new radiator (used less than 5 miles) and also installed a third fan.
Last moth I swaped to carb, so I pluged the throttle body coolant hose and the hose that was near to the distributor (rear intake manifold side).
Brand new belt tensioner....
What could be happening?
help please
the temperature grows quick from 150° to 230 and even higher (at idle and running) I notice that coolant droops to coolant reservoir (this coolant is cold). I disconnected the radiator inlet hose and saw that the coolant flow is intermitent....sometimes it flows, sometimes not
I pulled out the water pump, and didn't notice any impeller problem. I have a brand new radiator (used less than 5 miles) and also installed a third fan.
Last moth I swaped to carb, so I pluged the throttle body coolant hose and the hose that was near to the distributor (rear intake manifold side).
Brand new belt tensioner....
What could be happening?
help please
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Team Owner
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From: Cincinnati, Oh USA
If you didn't maintain the coolant sensor which was under the MAF, during idle the fan will not come on and coolant temp will keep going up. Underway (over 35 mph) with no thermostat you should experience too cold coolant temp. You should never run an engine without the thermostat.
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Le Mans Master
Joined: Dec 2006
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From: H-Town Texas
Not sure on the L98's, but did you block these hoses thus stopping coolant flow, or connect them retaining flow but by-passing throttle body? As I said, I'm not sure how this works on the l98, but on the LT4 I just connected the hoses that go into and from the TB to retain coolant flow.
The answer to this could be important.
Thread Starter
Intermediate
Joined: Aug 2008
Posts: 48
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I turn on fans direct from switch. fans are always working.
the hose that was on Throttle body is block. Im sure that my problem isnt the fans or thermostat. Maybe something with the hoses. I need your experience guys....help me...Its summer right here....rains will come in about 2 months.
the hose that was on Throttle body is block. Im sure that my problem isnt the fans or thermostat. Maybe something with the hoses. I need your experience guys....help me...Its summer right here....rains will come in about 2 months.
Le Mans Master
Joined: Aug 2000
Posts: 8,838
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From: Australia
No thermostat ,
Coolant moves too fast through engine so it doesn't pickup heat ; engine overheats
Also without back pressure from the thermostat ; pump can cavitate ( form air bubbles ) so it is not pumping anything; OVERHEAT
What inspired you to have fans on full time and no thermostat?
IF it did work engine would never get up to correct operating temp
Coolant moves too fast through engine so it doesn't pickup heat ; engine overheats
Also without back pressure from the thermostat ; pump can cavitate ( form air bubbles ) so it is not pumping anything; OVERHEAT
What inspired you to have fans on full time and no thermostat?
IF it did work engine would never get up to correct operating temp
Last edited by rodj; Feb 7, 2011 at 09:33 PM.
Le Mans Master
Joined: Dec 2006
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From: H-Town Texas
Step 1: Connect the hose that went into the TB directly to the one that went out of TB.
Step 2: Put a T-Stat in it.
Step 3: Check and/or replace Radiator pressure cap. Then bleed system for possible air pockets.
Step 4: Make sure you do not have coolant in oil or oil in coolant from a head gasket due to warpage from overheating.
You said it goes from 150 to 230+ really quick, how long does it take to get to 150?
Step 2: Put a T-Stat in it.
Step 3: Check and/or replace Radiator pressure cap. Then bleed system for possible air pockets.
Step 4: Make sure you do not have coolant in oil or oil in coolant from a head gasket due to warpage from overheating.
You said it goes from 150 to 230+ really quick, how long does it take to get to 150?
Le Mans Master
Joined: Aug 2000
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From: Australia
On a CORRECTLY functioning system ;hot water goes out the top hose ,through radiator , returns to block through bottom hoses and WP
As we speak I have a HSR equipped L98 idling in the garage with only the radiator hoses.
With the fans reprogrammed , it is happily cycling from 195 down to 180 and back up.
And it doesn't even have a radiator cap on the system, just a vent hose into a overflow bottle
Thread Starter
Intermediate
Joined: Aug 2008
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I found that my intake manifold is blocking this coolant passages. Looks like coolant flows from left head to the right.
on other forums people said that this coolant passages are not used. I dont this so, because when I was using the tpis big mouth, the coolant flowed between the heads....
ideas, sugestions will be appreciate
[IMG]
[/IMG]
on other forums people said that this coolant passages are not used. I dont this so, because when I was using the tpis big mouth, the coolant flowed between the heads....
ideas, sugestions will be appreciate
[IMG]
[/IMG]
