Hey all. Got a 87 Jimmy Sierra Classic with the 350 we bought in the spring. Havent driven it a lot due to a problem with the cooling if any one could give a few ideas would be appreciated. To start the thermostat had been replaced along with the fan clutch( or so I've been told). At an idle she never over heats but you go 5 miles down the road and she will start to get hot pretty darn quick. Last time she got out hot the upper and lower hose were reading about 190ish on my radar with the radiator underneath the pressure cap was around 220. Neither of the hoses are getting sucked in and there are no leaks so I think the cap is doing it's job. There is no antifreeze on the dipstick and it doesn't smell like antifreeze either. We also used a combustion leak test and found no problems. The water pump seems to be working because with the pressure cap off you can see water getting sucked down into the radiator when you step on the throttle. The fluid is disgusting looks like pong scum. We are going to change that. The only thing we have noticed is the large amount of air the fan is pushing out the front. Under the hood there is minimal airflow getting pushed into the engine bay. With my 94 k1500 you can feel and see the air move very well a small rag. Is it possible someone put a pusher fan on? The fan rotate counter close wise if you looking at it from the driver side fender. Any help or advice would be greatly appreciated. Thanks
CK5
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Cooling issue
- Thread starter 87jimny
- Start date
Ya got the wrong pitch direction fan.
Find a parts guy that understands the difference between a “k” series and a “V” series’87 model truck - yours is a “V” series.
Also, that’s a light-duty fan clutch - if wanted replace with a HD unit to match your correct fan pitch.
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Sure enough. That is the wrong fan setup.
make sure the clutch is correct direction as well.
I called it
The reason I called it was he said it has a serpentine belt and a v belt, which means the rotation is clockwise but if someone had replaced the fan and said it has serpentine belt, they would be given a reverse rotation.
THANK YOU ALL FOR YOUR ADVISE. We took the old blade off and found the problem with its on circle of death stamped on it. Ha ha. Might have found one from a junkyard about 30 minutes from where we live. It's off an 88 they tell me so we are going to give it a shot. Might even put a new pump on it just to be safe plus one of the bolts was missing and the threads on it are messed up. Now a friend has a blade off an 89 jimmy my question will that work or because it's off the serptine belt drive system will the pitch or the rotation be wrong? I'll attach 2 photos of the old blade and th3 jimmy has it sits. Thanks again all.
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That 88 if truck might be the same direction as that ford blade, you don't want that. If a Blazer, burb or Crew Cab, then 50/50 change either direction.
