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dh_bennison
04-07-2007, 07:52 AM
Hi,

I have a 96 205 with the LT1 engine. The last couple of times I have started it, the temp after about 5 mins rises to about 240 and the engine check light comes on. Then eventually (normally after a bit of reving in neutral) it drops very quickly back down to is normal temp approx 160. I have also noticed that when I start the engine initally the shower does not pump water constantly (although it is fine when the engine has been running for a while). As the shower is plumped to the cooling system I am assuming they are the same problem. My theroy is that is maybe a airlock but any suggestions would be welcomed.

Thanks

TMCNo1
04-07-2007, 08:07 AM
With the shower and the temp problem, I would look into a sticking thermostat if I were you.

bigmac
04-07-2007, 09:37 AM
I'm a big skeptic of "air lock" blockages. I'd be much more inclined to view it as a raw water pump problem - either a bad impeller or something blocking raw water output.

I would begin by changing the impeller (if you haven't already done so - surely you have...) and if that's intact check the transmission cooler for weeds or pieces of old impeller. If those things are negative, I would replace the thermostat.

cst573
04-07-2007, 09:39 AM
Im with #1, sounds like a sticking t-stat.
Pretty cheap fix.

WTRSK1R
04-07-2007, 10:06 AM
Have seen this exact issue on a '96 190 with the standard engine. The implellor was damaged, and until you revved up the engine, it would not move enough water to cool things down. (it could not pull water up from the lake) Once you revved it up, it had water flowing, and was fine at idle too. Swapped the impellor and everything was back to normal.

Check the impellor !

workless
04-07-2007, 10:33 AM
Sorry, but not all my life was spent with an MC. My "other" boat (87 SeaRay) has a 350 in it. The thermostat, as it would go bad, about every 5 or so years would start to stick closed(center pin that opens to allow water through at temp), this would happen at start-up and during operation as it got older, which would increase the eng temp. Then it would settle down and run at the set temp. This would happen periodically until I either changed the stat or it failed completely. Watch NAPA, the last time I went to replace it (last year) the new replacement was not all stainless, which matters unless you have a closed loop system.
And thanks for the tips on the window!
Happy Easter!

Jim@BAWS
04-07-2007, 10:39 AM
Hi,

I have a 96 205 with the LT1 engine. The last couple of times I have started it, the temp after about 5 mins rises to about 240 and the engine check light comes on. Then eventually (normally after a bit of reving in neutral) it drops very quickly back down to is normal temp approx 160. I have also noticed that when I start the engine initally the shower does not pump water constantly (although it is fine when the engine has been running for a while). As the shower is plumped to the cooling system I am assuming they are the same problem. My theroy is that is maybe a airlock but any suggestions would be welcomed.

Thanks

Take the boat out of the water. Run it on a garden hose, within 10 sec there should be water coming out of the exhaust. No WATER NO raw water pump/ impeller. The LT-1 has 2 thermostats not one. If you have been running that LT-1 in salt without 100% closed cooling that is another issue. The transcooler is usually before the raw water pump. You could check that for blockage.

DO NOT USE AN AUTOMOTIVE THERMOSTAT.

Jim@BAWS

Jaysonsmith
04-15-2007, 01:12 PM
I also had a problem like this with my 98. Mine was a clogged transmission cooler. It's inline from the intake. I now check it every Spring. Lot's of pine needles & junk in the watre down here.

Jayson

gjhammond
04-30-2007, 11:32 PM
Take the boat out of the water. Run it on a garden hose, within 10 sec there should be water coming out of the exhaust. No WATER NO raw water pump/ impeller. The LT-1 has 2 thermostats not one. If you have been running that LT-1 in salt without 100% closed cooling that is another issue. The transcooler is usually before the raw water pump. You could check that for blockage.

DO NOT USE AN AUTOMOTIVE THERMOSTAT.

Jim@BAWS

Where are the t-stats located? I am sure one is in the usual Chevy location, but not sure of the other one. When I look at my cooling line routing I see where the intake line runs thru a "block or case" on the trans on my 96 Maristar, is this the impeller location? I don't see a pump like I had on my previous inboard that was belt driven.

Jaysonsmith
10-25-2007, 10:27 PM
Do you know where the two thermos are on a 98 PS 205 with LT1?