New motor running hot

[drgeometry]

Just replaced the 1.6D motor in my 1981 VW T2.5 with an identical one, in an effort to solve overheating and high-pressure issues. Coolant pressure now seems fine but engine temp is running high, at exactly half way on the gage. Heater is warm. Radiator is cold. Mechanic is a friend so I trust he's doing his best but this is the first time he's worked on an old / rear-engine VW bus. Electrical contacts on the radiator thermostat were cleaned. I reviewed with him how to bleed the system. There does seem to be some electrical short circuiting as my voltage meter flickers on and off as I drive and the 12v power port also flickers on and off. Should I start replacing fuses or the fuse panel? Could the radiator itself be clogged? Or is it okay for the engine to run at this temp?

[Robsey]

Intermittent power...

On a normal car, I would check tightness of battery terminals.

On these old busses, I would check the earth crowns on the left side A pillar.

Also bear in mind 43 year old electrics.
All wires and connectors need checking and a minimum of cleaning.

As for high temperature, I was of the opinion that "just to the right of half way" is well within the normal range.

[drgeometry]

Amazing. She used to run nice and cool at no higher than a quarter up the gage but if half way is not to worry about, then I'm not going to. Thanks for the insight. My next project will be cleaning all terminals. Fun fun. Sandpaper is all I need for that project or do I soak elements in some kind of de-oxidizing liquid? 

[cobblers]

Anything between 1/2 and 2/3rds up the scale is normal operating temperature - your old engine was probably running too cold. 

[Robsey]

Here you go from the horses mouth...
Or at least from the 1983 user manual.



If you get the red flashing temperature led, and if everything else appears okay, then the usual thing to check is the shortage indicator relay - on the A pillar somewhere near the earth crowns on it's own little socket.

But if the led stays off during normal running, then you shouldn't have anything to worry about.

[drgeometry]

Thank you so much!!

[Robsey]

You are most welcome.

I didn't answer your question in your reply.
What you use to clean or repair your connections depends on the state of your crimps and crowns.

Initially I cut off and crimped / soldered on new female spades, but then last year....

If you are doing the earth crowns, then you could go virtually maintenance-free.

An idea shared by Ian (silverbullet) was to get rid of the crowns altogether.

Replace all the female spades with loops.
(I crimped and soldered for extra security).

Then drill and crimp in two riv-nuts. (Sometime called 'Clinch nuts').
Think I used M5 threaded inserts.
And bolt the loops to the A pillar.
A couple of M5 x 20 hex head bolts and shake proof washers should do the trick.
(I happened to use cap-heads on my van).



And then smear on vaseline (petroleum jelly) or copper grease (coppaslip) to keep the damp elements out.

As for the coolant shortage indicator relay...
I forgot to say that it should have the number 42 or 43 printed on it.



The relay bracket is located where you see the upside-down 'T' on the pillar.

The two holes below it are where the earth crown were located.

Oops - looks like my upper earth bolt / riv-nut is too high.
Not a problem, as I converted my van to the later CE1 fusebox.