1989 Corvette w/L98 TPI
Thread Starter
Cruising
Joined: Jul 2011
Posts: 14
Likes: 0
From: MT
1989 Corvette w/L98 TPI
Just took ownership of my beauty, lifted the hood and found the engine coolant overflow looked more like swamp water than coolant, flushed the radiator, replaced coolant. now the temp is 225, per forum this is normal. My question is a simple one, what else would you recomend for my Corevette?
It was mothballed (sat in a garage for 2 years) seldom was the engine turned over during that time. I have purchased a quick disconnect for the battery because I seem to have a power drain, battery was drained after sitting for two weeks.. I can live with that. Next to an oil change what else would the experts of the Corevette forum suggest. clean the injectors? I noticed the transmission pan seal has a small leak. But other then that she loves the road and I love my Sportscar.
It was mothballed (sat in a garage for 2 years) seldom was the engine turned over during that time. I have purchased a quick disconnect for the battery because I seem to have a power drain, battery was drained after sitting for two weeks.. I can live with that. Next to an oil change what else would the experts of the Corevette forum suggest. clean the injectors? I noticed the transmission pan seal has a small leak. But other then that she loves the road and I love my Sportscar.
Le Mans Master
Joined: Jun 2006
Posts: 5,642
Likes: 5
From: One day you're a Comet...the next day you're dust... Arkansas
If it's an auto flush and refill trans fluid, replace power steering fluid with Valvoline high millage fluid and change the oil, and filter. I use Valvoline synthetic blend 5W-30. Dino is fine as well, that is per the owners manual. You can't successfully clean the original injectors. If it runs well leave them alone.
Drifting
Joined: Aug 2006
Posts: 1,624
Likes: 2
From: Canandaigua New York
Pull the radiator shroud and check for leaves, bags,small branches and little dead critters.
You'd be amazed what gets sucked up into the radiator from the road.
My car was only getting slight hot on a warm day. Checked the air dam from below and found 5 tree leaves the size of my hand almost totally blocking the radiator.
My car was running at 190 to 195 (not really hot) but now rarely goes over 180.
You'd be amazed what gets sucked up into the radiator from the road.
My car was only getting slight hot on a warm day. Checked the air dam from below and found 5 tree leaves the size of my hand almost totally blocking the radiator.
My car was running at 190 to 195 (not really hot) but now rarely goes over 180.
Le Mans Master
Joined: Dec 2000
Posts: 7,839
Likes: 22
From: San Diego, Ca
Crappy looking coolant is often endemic to the '89 and caused because the head gasket is weeping (exhaust) at #7 (a lot were failing around 25,000 miles). Pull that plug and compare it to #6 and do a leakdown test. Make sure the heater core isn't plugged up too and because galvanic corrosion wrecks havoc on all of the water passageways, I'd make sure you got everything out of it which means disconnecting the oil cooler hose at the filter and the knock sensor so that the Block can drain. Also look for an intake manifold leak near the thermostat. GM's Service Bulletin identifies intake leaks as the cause of the corrosion which eats of the head gasket. I wouldn't buy (another) '89 without doing all of this or asking if the head (and intake) gaskets had been replaced no matter how good it looked, particularly if had less than 50,000 miles.
As to coolant temps, if the cooling system is clean and the a/c works, running the a/c will keep those temps 8 to 10 degrees below the non-a/c threshold for fan operation at idle and low speeds. If it doesn't, something else is up. Cruise temps should be at the thermostat or close to it - 195.
As to coolant temps, if the cooling system is clean and the a/c works, running the a/c will keep those temps 8 to 10 degrees below the non-a/c threshold for fan operation at idle and low speeds. If it doesn't, something else is up. Cruise temps should be at the thermostat or close to it - 195.
Instructor
Joined: May 2011
Posts: 103
Likes: 2
Mine also looked like swamp water ( I think it was just poor maintenance by the P.O.). I cleaned everything out, changed hoses, and installed a 160 degree thermostat. Doesnt get above 170 degrees going down the hiway, it will still climb in traffic though.
And a basic tune up wouldn't hurt either.
And a basic tune up wouldn't hurt either.
Racer
Joined: Mar 2011
Posts: 296
Likes: 0
From: Derby (Wichita area) KS
Crappy looking coolant is often endemic to the '89 and caused because the head gasket is weeping (exhaust) at #7 (a lot were failing around 25,000 miles). Pull that plug and compare it to #6 and do a leakdown test. Make sure the heater core isn't plugged up too and because galvanic corrosion wrecks havoc on all of the water passageways, I'd make sure you got everything out of it which means disconnecting the oil cooler hose at the filter and the knock sensor so that the Block can drain. Also look for an intake manifold leak near the thermostat. GM's Service Bulletin identifies intake leaks as the cause of the corrosion which eats of the head gasket. I wouldn't buy (another) '89 without doing all of this or asking if the head (and intake) gaskets had been replaced no matter how good it looked, particularly if had less than 50,000 miles.
As to coolant temps, if the cooling system is clean and the a/c works, running the a/c will keep those temps 8 to 10 degrees below the non-a/c threshold for fan operation at idle and low speeds. If it doesn't, something else is up. Cruise temps should be at the thermostat or close to it - 195.
As to coolant temps, if the cooling system is clean and the a/c works, running the a/c will keep those temps 8 to 10 degrees below the non-a/c threshold for fan operation at idle and low speeds. If it doesn't, something else is up. Cruise temps should be at the thermostat or close to it - 195.
This is all ood info. I purchased a low mile (60k) 89 back in January and recently replaced head gaskets for the #7 issue. I was lucky, mine failed to the outside. I has taken a lot of hours and I am still trouble shooting some rough running which I suspect is a vacuum leak but haven't found yet.
One question though...is there something about the 89 model that causes failures in this area? Is there any real differenc between an alum. head L98 from 86 to 91 with regard to cooling/headgasket issues?
Other than a good flush and use of 50/50 distilled water & green coolant is there anything else I can do to extend the life of the cooling system?
BTW...this forum has been an invaluable asset during this project. I haven't needed to post questions since everything I encountered had been covered in detail and was availabe with a search. Thanks to all who've taken time to answer questions in the past and rest assured the info is still being used.
Thanks,
Dave
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Le Mans Master
Joined: Jul 2007
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From: No HOA, New Hampshire
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