Fuel Injection Pump Coolant Tower

[Harry]

This tower (the warm running device I believe) has two coolant lines going to it and the tower is attached to the FIP with two screws.  Inside is the WRD mechanism that adjusts fuel mixture based on engine temperature as indicated by the coolant temperature (as I understand it).

So the cavity within this tower is wetted with coolant, and the two screws hold it down tightly against the FIP.  My question is what is the seal between the FIP and the tower to be certain that there are no coolant leaks?  I expect that a coolant leak here could introduce coolant into the FIP (not good)?

Harry

[ja17]

Similar to other metal fittings, the machined surfaces of the parts do not need a seal. Some owners use a thin film of sealant for insurance.

[Pawel66]

I looked through a lot of posts when I was working on WRD in my car. Based on what I read I did apply sealant between the thermostat housing and the WRD valve housing. This was, as you say, to protect valve from coolant dripping in as coolant may make the valve area corroded and the valve would bind eventually.

Where the WRD valve housing attaches to FIP - I used no sealant, there are just oval shims there.

[Harry]

Thanks men.  This is exactly what I did.

[wwheeler]

The other advantage with applying a sealer to that seat is that you can remove the housing with the bulb without draining the coolant. Handy if you are adjusting the round shims on the air valve or just cleaning things up a bit. Be sure to remove the radiator cap to relieve any pressure first.

[Benz Dr.]

The 230SL thermostat has a small seal at the bottom and the 280 style has a metal ring. I use a bit of sealer on both of them.