RAt Rant

[Andy D]

Rassen frassen Rat smells of gear oil and the RR is hot to touch. I suspect a frozen E brake cable. . I discovered this 20 miles from home., but drove home without incident. In fact, the hub was merely warm when I checked it. More later.

Harbor Freight float charger had the battery at 13.xx V. I have a V meter hitched to the battery to monitor how low the drops go. I plumbed depths of the radiator. !/2 full of cavitated coolant. No big deal, there is a full jug of 50/50 in the bed. The over flow tank and the buffered water temp gauge had me in a fool's paradise. It is a non pressurized overflow. Not an expansion tank This is incidental to the frozen brake issue.

I picked up the factoid about the over flow in passing here and decided to check. Just another leak to be monitored.

 

[enjr44]

I plumbed depths of the radiator. !/2 full of cavitated coolant. The over flow tank and the buffered water temp gauge had me in a fool's paradise. It is a non pressurized overflow.

I picked up the factoid about the over flow in passing here and decided to check. Just another leak to be monitored.

Andy,
Can you point me to the factoid on the over flow and coolant cavitation issue. I may have a similar issue with my 91 4L.

Good around town. On the hi-way it will throw about a pint or more of coolant into the overflow tank. Sucks it right back at idle. It will do it faster than the overflow line can handle so a small amount will come out of the rad cap.

Thanks, Ed

 

[snake]

enjr, yours sounds like a bad rad cap. The spring gets weak and they let water flow too easily.

 

[Andy D]

The fact is that the overflow tank isn't a pressurized expansion tank. So its siphon may or maynot work. The coolant level in the OT is right on the cold mark. A check of the radiator tank revealed it to be half empty. The system with the cap on has run fine with no signs of trouble for 2 yrs.

 

[enjr44]

The fact is that the overflow tank isn't a pressurized expansion tank. So its siphon may or maynot work. The coolant level in the OT is right on the cold mark. A check of the radiator tank revealed it to be half empty. The system with the cap on has run fine with no signs of trouble for 2 yrs.

Andy,
That is the way I first found mine. Except the overflow tank was full to the top and the rad was way low. What I noticed was that as the engine cooled the top rad hose was completely collapsed (I mean sucked completely flat. My first thoughts were a bad head gasket or a cracked something; but, I don’t have any other symptoms. Still haven't ruled that out though.

I changed the coolant, rad cap, thermostat, and hose. I probably didn’t need the thermostat; but, the coolant needed changing. Anyway, the rad stays full and the hose stays round now. So I figured the cap was bad. Now, the only problem I have is like I said. On the highway, it may (not always) push maybe 3 inches worth of coolant into the overflow tank and a little coolant out past the cap. When you let it idle down it sucks it back and refills the rad. My temp gauge goes up to normal, then it will go back down about three needle widths and then back up and keep cycling like that.

So, when you mentioned cavitation that got my attention because cavitation would separate the water molecules into oxygen and nitrogen and that could/would push the coolant out of the rad.

Ed

 

[Andy D]

the stuff was like froth from warm root beer. It was being whipped by the water pump pumping at partial volume. It now took the full gallon. The Temp gauge does run cooler, so maybe it works well enough to pay attention to.

I'm glad I discovered it. I opened the cap for the first time in over 2yrs. It was heading for an overheat. One more thing to monitor and try to figure out where the leak is.