1998 U-320 M11 Celect Plus 450 HP engine
I searched the forums but only found one response, and want to double check.
Coolant in the metal engine coolant tank is about half full (well above the sight glass but a few inches below the filler neck). Overflow tank is above the cold line. New radiator and on a six day drive the engine coolant temp was fine. No leaks in system when parked.
Should coolant be added to the coolant tank, and to what level?
About to start a long drive back home and am checking fluids before departure.
Thanks,
Chris
Chris,
YES.
If you have an overflow tank, it should be up to the cold level when cold, hot level when hot, WITH THE RADIATOR/METAL TANK (basically anything on the engine-side of the pressure cap) full.
After servicing the cooling system, it is normal for it to take a couple of "top offs" to get all the air out of the system.
Make sure your overflow tank is set up to return the coolant to the metal tank when the engine cools off after running. We had a recent discussion with another member who was losing coolant because he was missing a simple plastic tube in his overflow tank.
Overheating Help: FT GV with Chevy 454 on P-30 Chassis '87 (http://www.foreforums.com/index.php?topic=32301.msg288676#msg288676)
Thank you both for your replies.
I will top off the metal coolant tank.
The plastic overflow tank has two hoses:
- one on the bottom of the plastic tank that returns to the filler neck on the metal tank
- one on the top of the plastic tank that runs down the outside of the plastic tank and is open on the end to allow coolant to pour out if the plastic bottle gets too full
I just had mine flushed and filled. Day one, the engine rand about 9 degrees warm. When stopping for the day, topped up the plastic reservoir to the "HOT" level. In the morning, engine sucked in quite a bit as it cooled. Day two, rand about 3 degrees warm. Repeat process. Day three, ran at tHe proper temp and no coolant in the reservoir was required. Seems you have to work on "burping" these systems.
When we say to fill the steel radiator tank, we mean really full-right up to the level of the overflow tank tube.
Yup, My nipple @ the metal tank for the hose to the overflow tank had a tiny crack @ the tank neck/cap. This caused the system to not create a vacuum & suck the coolant back into the system when the engine cooled..
Is there supposed to be a tube inside the overflow tank? I've been losing coolant and assumed it was because I had recently replaced my radiator and it was still purging the air. I went back to check and just now found that my over flow tank cap is split. Does anyone know where I can get a replacement?
It returns out the bottom of the overflow tank no tube needed.
Two different types of overflow tanks. Either one accomplishes the same purpose: returns the captured liquid to the radiator.
I bought an exact replacement once from Foretravel. Pricey at around 60 bucks. Might be able to find it cheaper elsewhere.
jor
If you are just after the cap, there have been posts about them. Here is one of them. It is an old post but has the part number
Radiator Overflow cap found (http://www.foreforums.com/index.php?topic=3494.msg12867#msg12867)
Howdy Sven, I did like Beerslayer_24: Plastic overflo tank cap (http://www.foreforums.com/index.php?topic=28088.msg232393#msg232393)
and bought a spare from Roger: Expansion Tank Replacement Cap - Vented (http://www.parts.rvhydronicheaterrepair.com/Expansion-Tank-Replacement-Cap-PLE-HYD-001-Vented-Cap-PLE-HYD-001-Vented.htm)
Good Luck, Dave A
A quick follow up.
It turns out we did have a couple leaks in components on the metal coolant tank that were revealed after topping off the tank, firing up the engine, and inspecting.
1) The cap on the metal coolant tank was the wrong type and leaked - one drip every five seconds. It was a 10# cap without a second gasket at the top. The correct cap is a 15# cap with a second gasket. Replaced the cap and the drips stopped. Per Foretravel parts dept, the correct coolant tank cap is NAPA part #: 703-1427
2) the rubber overflow tube (leading from the nipple on the filler neck to the plastic over flow bottle) had a split in it at the barbed nipple on the filler neck of the metal tank. The bad section was cut off, a constant tension clamp was added to the tube, and the plastic hose supports screwed into the back wall were redone so the hose didn't bend at the nipple and to provide more slack.
Chris