2.5 Engine Shake

[marc61]

Hi

Last night coming down the A1 at speed, I suddenly lost all electrics, pulled over, bonnet up, found earth lead cables had melted their way out of batttery connection. Today found it was the positive cable to starter that was shorting to earth and have now fixed it and car is running. But engine is shaking big time at idle and at higher revs.

Not really driveable. Does anyone know what might have happened or what I can check? Its not so much loss of power as a regular violent shake of engine.

Engine was really sweet and car is very good, so would appreciate any advice.

Thanks

Marc

[xmexclusive]

Hi Marc

I think that I would be checking out the engine mounts.
There are 3 on the drivers side -
upper - slightly below and behind the strut head,
lower - bolted to subframe,
middle - bolted to underside of main chassis at engine centre point.
There is one hanging mount passenger side by the battery box.
First watch these with the engine running to see if the nature of the movement points you to one particular mount.
Check the fixing bolts then the rubber of the mounts.
Surprised that this type of movement could tear out the battery connections.
That suggests that it is either the single passenger side mount or just two seperate problems that happen to have coincided.
Citroen battery lead crimps are not the best workmanship and do sometimes burn out.

John

[marc61]

Thanks, but having investigated some more I'm pretty sure the head gasket has gone now with gas bubbles coming into water in header tank, more when I rev. Not many as yet, but suspect if I try to drive it it will get worse.

Guess it must have overheated when it came to sudden stop, no fans, no water pump action, hot day. If thats the case it really surprises me that a head gasket can go that easily? But there we go I have bubbles in the water and an engine with a big nervous twitch now!

Have read the Haynes manual and am wondering whether to take engine out and have a go at removing head. Looks like theres very little space to get it off in situ as far as I can see, so better to take the whole lump out. If anyone has any suggestions as best course of action please let me know.

Marc

[xmexclusive]

Sorry to hear the cause.
There is an engine been on ebay for a while now for £250.
Location is near Chester.
Know simply because it is on my watch list.
Will look up the item number if you cannot find it.
2.5 heads have a reputation for often dying when the head gasket goes.

John

[noz]

Hi Marc,

Thats a fair old mix of symptoms you have there. I've been trying to piece together your info to see if there's a common thread but I'm afraid this is the best I can do.

The melting of the cables in the negative battery terminal can certainly be explained as a result of the shorting positive cable to the starter motor. One question I have is, what did you have to remove/disturb to get access to the positive cable to the starter? I take it the radiator, intercooler and intercooler bracket had to be removed? If so, I presume you drained the coolant system?

Is the starter engaging and disengaging cleanly? Did you remove the starter? How did the positive cable get loose enough to short to earth in the first place?

To get at the starter did you disturb the fuel lines? Did you disconnect the fuel filter?

Did you do any other maintenance or did anything else happen around the same time?


The engine shaking could be down to air bubbles in the fuel. Check all the fuel line connections which were broken during the time you gained access to the starter.

If you've had the system drained and refilled that could explain the bubbles. The 2.5TD has a bit of a reputation in not clearing the air from the system very efficiently after a drain down and refill.

If you could shed a bit more light on the above it might help to pinpoint your troubles more accurately.

cheers

noz

ps
the 2.5TD head can be doe with the engine in situ.