220v rebuilt engine runs too warm ?

[OrMar]

I had my 3b engine rebuilt (H-profile conrods, new piston rings, new rod-bearings, 7a exhaust cam, 031 BPV) by a trusted mechanic. However, he's not an Audi specialist.
Engine now runs constantly at 110C, no matter if idling, in heavy traffic, or driving 70 km/h in 4. gear. Fan kicks in occasionally and hold the temperature there, but I have bad feeling it's on the edge of boiling. What are the usual things behind such a behavior ?

Also, with full throtle, after boost reach 0.5 bar, some ugly vibrations start and boost dances around 0.5 bar (I have separate boost gauge), few milimeters up and down. Is this surge/flutter/chatter or what, and what could be causing it ?
Could it happend that he connected something wrong ?

Thank you,
Mario

[s2driveruk]

110c as a constant temp....? I'd be looking at coolant temp sensors initially

[OrMar]

You mean that I'm might be getting wrong info on gauge, or that fan kicks in too late ?

Thanks,
Mario

[s2driveruk]

actually wonder if the sensor is faulty or you have one with too higher temperature value installed?

[lini]

I bet VAG-COM knows the answer if its too hot or only a sensor problem.

[chezz]

Has the thermostat been fitted incorrectly?The engine becomes so fiercely hot that you cannot physically go anywhere near to it, when this very simple mistake has been made.
Check the temperature of the lower hose, Is it cool?

[OrMar]

Has the thermostat been fitted incorrectly?The engine becomes so fiercely hot that you cannot physically go anywhere near to it, when this very simple mistake has been made.
Check the temperature of the lower hose, Is it cool?

How is it possible to fit thermostat incorrectly ? Where should the arrow on thermostat point to ?
Lower hose is warm.

At one point, fan fuse blew and car was spilling boiling water throuh expansion tank, so I guess water is circulating.


Mario

[OrMar]

I bet VAG-COM knows the answer if its too hot or only a sensor problem.

By comparing ECU-sensor output to instrument ?

Mario

[OrMar]

actually wonder if the sensor is faulty or you have one with too higher temperature value installed?

Could be - both temp. sensors are new. If fan controled by ECU, or by thermoswitch directly ?

Mario

[Knight Rider S4]

As said i would plug in vag.com and scan for codes and use measuring blocks to see what the actual temp is ...Sounds like you might have a faulty sender or your cap on expansion tank is goosed

[chezz]

How is it possible to fit thermostat incorrectly ? Where should the arrow on thermostat point to ?
Lower hose is warm.

At one point, fan fuse blew and car was spilling boiling water throuh expansion tank, so I guess water is circulating.


Mario

The reason it is spilling boiling water out through the expasion tank is definitely due to the thermostat being installed incorrectly. The system is not circulating...it is way past boiling temperature in the block and it can only go move back up through the block and out of the expansion tank.The next thing to occur will be your top hose will blow.
The engine is at risk risk of seizing as you have in effect absolutely no means of cooling your engine and the temperature readings will be correct. DO NOT drive your car!
The spring side of the thermostat should sit in the block.
For the moment I would remove it completely.Thermostat may be jammed shut, but I doubt it.

[AUDIS2avant]

just a question here, which way does the water run thru the termostat, from block and out or from hose to block?

[chezz]

just a question here, which way does the water run thru the termostat, from block and out or from hose to block?

Heated fluids exit out of the block/thermostat housing and through the rad, once cooled,
they re-enter the head and obviously absorb the heat and reduce the temperature and so on...

[Mikes2]

if it is running at 110 degrees on the gauge, and the fan is not running, then you're not getting 110 degrees in your radiator or the fan would run all the time.

Hate to say it but water out the expansion tank could be a head gasket issue. Seen it recently

[rtg-andy]

has the radiator been bled thoroughly? could be an air lock