Tickover Rattle, Diagnosis

[bobtee]

Thanks for the instant reply noz ,where did you get that name from?
Ihope the rattle is not from the tappet .
The noise is only apparent to me when inside the car and at tickover as you increase revs it goes away driving or stationery.
Ihave been listening to it a bit more closely now and the noise seems to get less acute after a few miles and if i open the drivers window ,I have been around the engine space and pulled and pushed various items to no avail,i have also used a screwdriver as a stethescope on different parts and can find no real difference in mechanical noises ie no heavy taps or ticks etc,Thats what makes me belive its not a serious mechanical problem. the engine sounds ok at high revs .
Ihoped it was a common problem on the xm and would turn out to be a loose bumper or something ,o well carry on looking .
The clutch is cable operated on this one .
Do you know if the clutch can be a problem on this car, my previous xantia had problem with the cable clip snapping -----ended up having new clutch kit and cable just to make sure think the diaphram spring got really hard.
Thanks for the advice about the matrix display await your info with interest.
Thanks again for the reply i hope this post is in a more appropriate section please have patience with me i may get it right yet.
Best regards Bob

[Peter.N.]

I would concur fully with Noz on his diagnosis of noisy hydraulic tappets, as three out of the four 2.1 TDs I have owned have had this problem. They can make a heck of a rattle when started from cold but stop at about 2,000 rpm although the noise will often return when the revs drop, especially on a cold engine. Strangly, it always seems worse, directly after an oil change and then quietens as the miles progress. You could try some engine flushing oil at the next oil change.

To hopefully put your mind at rest, I have never had to take any further action as the noise has always eventually gone off, only to return (sometimes) at another cold start.

Pity in some ways I havn't got the same problem with mine as at present I have the camshaft carrier and all the tappets and rockers lying in a neat row on the bench as I am still trying to get the head off to replace the gasket.

Peter.N.

[noz]

Bob,

yeah, the name's a bit of a long story. Real name's Norrie but too many times when registering with forums it's already taken so its unusual to make sure I get registered first time without a lot of toing and froing. Sort of stuck since.

Need a bit more info to definitely pin it on a tappet. Need to know the frequency relative to the engine rpm. If one tappet only then the tapping noise should be a half of the engine rpm.

Could it be that the exhaust is touching the bodywork underneath the car? That can generate some frightening noises and vibration inside the cab but the problems easily solved. It will be engine rpm related and temperature related.

Sorry no info on the clutch cable. You're right about the clip the same design exists with the inherent problems.

I'll get back in touch re Dot Matrix.

Cheers

noz

[bobtee]

Hello noz and peter thanks for the replies.
Food for thought i think ,that doesent sound right.
Noz the frequency of the rattle is toooooo fast to count i estimate its about the same as the rpm, it does seem to increase intime with the engine rev increase.
Still cant hear anything under the bonnet or outside the car but i am going a bit deaf.
I will try to have alook under the car this weekend and check the exhaust.
Is the cylinder head a problem to get off peter ,there seems to be a lot of room under there compared to the xantia but ive never done that so good luck.
thanks again will come back later.
Best regards Bob.

[Peter.N.]

Hi again Bob

If you can't hear it outside the car then it probably isn't tappets, could be general engine noise being transmitted into the cabin, perhaps via the clutch cable, check the isolating components at the gearbox end, or maybe something is making contact with the bulkhead. I have a strange rattle on mine at certain engine revs which sounds like something loosly touching the bulkhead behind the engine,but I havn't been able to find it, will be interesting to see if it is still there when I put it back together

Removing the cylinder head is not for the faint hearted, its taken me the best part of three days to get it off and it's now at an engineering workshop waiting to be skimmed, will be ready tommorrow. I certainly won't be doing it again! Incidentally, if you are reading this Noz, the head gasket looks as though its been eaten by rats, never in my life have I seen one in this condition,any thoughts?

Peter.N.

[noz]

Peter,

has it eaten through the metal rings around the cylinders (on the gasket that is)? If so, I had something similar on mine. I replaced the head once without skimming but that was a big mistake. The island of material between cyls 1&2 and 3&4 was badly worn and even with a new gasket it let gas by and destroyed the gasket.

Another possibility is the injectors. for both cars now I've taken the injectors to be tested. When they're put on the pressure tester the result is devastating. INstead of a nice conical spray with good atomisation the jet of fuel came out as a single squirt with no atomisation at all. Funny though, the release pressure was about right at 178Bar. The melted piston in my '95 2.5 was definitely down to bad combustion because of a faulty injector. Check those injectors out.

It cost me £70 just last week to have them refurbished with new nozzles. The guy would probably do it by post if you wished. Either that or send them to me and I'll take them in.

Cheers

noz

This post has been edited by noz on March 11, 2005 08:22 am

[Peter.N.]

Hi Noz

No, its not round the cylinders it is mostly in the water ways, looks as though someone has topped the radiator up with battery acid! I got the head back today, he only had to take 10 thou off so was fairly flat, but he drew my attention to several areas where the head was corroded, mainly, again around the water ways.

GFS dont have head gaskets for Mk2s, so I have had to order one from Citroen at £60+! I have been driving my wifes ZX, its not bad but I am looking forward to getting mine back on the road.

Peter.