Colling system problems
Thread Starter
Registered User
Joined: Jun 2007
Posts: 4
Likes: 0
Colling system problems I just got done swapping a '00 LS1/ 4L60 into my '70 chevy pickup. Everything is great except for the cooling system. I'm using a new stock style 4 row radiator and dual electric fans. I'm also using a VDO sending unit I got from Napa Auto Parts in the rear of the passenger side head w/ the stock gauge. I first ran it w/ the stock 195F themostat and it got to the top of the normal range on the gauge (no numbers on the stock gauge), so I shut it off. Thinking it was stuck, I replaced the thermstat with a 160F and tried it again... same thing. So I took the thermostat out and ran it. I drove it to get exhaust hooked up (15 miles roung trip) it seemed to be fine, but was creeping up by the time I returned home. I heard thats not good to run engines without a thermostat, so I'd like to get this solved. Whether it's got a thermostat in it or not, each time if I take the rad cap off- I dont see any circulation in there. I have filled the system through the top hose everytime, because I heard this is best way to fill them. Is it not "burping" all of the air out? Is the factory gauge not compatible w/ the sending unit? Is the WP not pumping (doesent seem likely)? Thinking about getting a cheap temp gauge (w/ numbers) and hooking it to sending unit and see what it says. Any ideas?
Don't trust the gauge! The scanner tells us the motor is at 195* when the gauge says we are at the high end of normal. Use a infrared thermometer to check the temp, and hook up a scanner if you can. It will tell you what the temp actually is, and you can get it set in your mind where the gauge should read.
Thread Starter
Registered User
Joined: Jun 2007
Posts: 4
Likes: 0
I got me a cheap mechanical tempgauge today and its staying under 160F, so it was never really overheating. I'd like to stay w/ the stock gauges so, other than the old skool big ones that were used on the Chevys, is there a sending unit available that would communicate w/ the stock gauge correctly and be small enough to fit in 1/4NPT hole? I'm sure there's someone out there that has an LS1 setup w/ stock gauges.....?
We used the S&P adapter for the 1/2-14 sender. It works, but it isn't as accurate as I would prefer. I like it when the needle is straight up on the gauge at operating temp, this one is a little to the right of up. We can live with it.
