Engine Timing inlet camwheel
 

Rover 75 2.5l
I inherited this car from my brother who was offered only scrap price when trading it in for a new electric machine. Good luck to him I say! On listening to the engine sound i realised that there was a problem with timing; it just didn't sound right. I hvae now got to the nitty gritty problem. Who ever fitted the last timing belt not only fitted a belt which was too long but also lost the engine timing. My problem is that he fitted the camwheel on the rear shaft with the part number facing inwards towards the engine block and the cam wheel on the front shaft he fitted the cam wheel with the part number facing out from the engine block. Obviously he was 50% correct!! I have a set of the proper timing tools. When I fit the locking tool to the front shaft (ie the one wth the part number facing out wards) and I check the rear cam wheel marks I find the inlet cam mark on the rear camwheelat about 20 degrees to the left of the correct position whereas the exhaust cam wheel mark is correct. What do I do? This is the first time that I have worked on this car so am not overtly familiar with it. Advice would be gratefully received.

Fred

Engine timing inlet camwheel
 

I think that I have solved this. The correct way round for the cam wheel is with the part number towards the engine block. Everything seems to line up then. Proof of the puddnig will come when I bar the engine over. Many thanks to any one who read this pearl of wisdom.

#Fred

Well done ; that didn't take long ! :}
Did you get the right size belt ?

Hello Fred,

It's been discovered that, with the flywheel/drive plate pin inserted on a correctly timed engine, the rear sprocket marks don't quite align. This isn't a fault and it isn't covered by the workshop manuals.

So, to remove the rear sprockets with their belt, it is first necessary to remove the flywheel/drive plate pin and turn the engine very slightly until the rear sprocket marks align.

I thought that you'd like to know that otherwise you'll think it's impossible to time your engine correctly. :}

By the way Fred, how did you come to the conclusion that the front belt is too long?

Simon

Hello Simon sorry for my slow reply. I came to the conclusion that the old belt was too long because the new belt supplied by Rimmers was much shorter and just fitted beautifully. I have not finished this job just yet but hope to do so within the next few weeks. If the old belt stretched the timing must have been out by a mile . There was always the possibility that a slack belt could jump a tooth. Stll learning about this beautiful engine.

Fred

Engine timing inlet camwheel
 

Hello Simon sorry for my slow reply. I came to the conclusion that the old belt was too long because the new belt supplied by Rimmers was much shorter and just fitted beautifully. I have not finished this job just yet but hope to do so within the next few weeks. If the old belt stretched the timing must have been out by a mile . There was always the possibility that a slack belt could jump a tooth. Stll learning about this beautiful engine.

Fred

In that event Fred your engine would run very badly or not at all. I'm not convinced by this stretching theory. If that were to happen, the enlarged teeth would no longer grip the sprocket wheels and the tensioner would run out of adjustment with catastrophic results.

Having done it myself, comparing the length of two belts is actually quite difficult with any degree of accuracy. You'll know that they are not pliable and the new one will tend to have adopted the shape dictated by its packaging. If you followed this subject on the forum last year you'll remember that my belts had covered the maximum mileage recommended by MG Rover and had exceeded the time limit by over three times. I found no evidence of stretching on any of them.

I hope that the rest of the job goes well for you Fred.

Simon

Hi Simon. I measured the two belts very carefully and the original belt was one and a quarter inches longer. It literally fell off the pulleys/sprockets as soon as I released the tensioner. i reckon my brother was a very lucky man! I have to admit that replacing the exhaust cam cap seals is the most difficult part of this job. I think it is made more difficult because the engine moves away from you as soon as you start to squeeze them in. Perhaps one should wait until the engine mount has been replaced but access is probably very difficult then.

Fred

I've done many belt changes on the KV6 (always with the locking/setting tools, just my personal choice) & never known the old belts to be 'stretched' to any extent, especially the amount mentioned here. The belts are the same for the 2.0ltr & 2.5ltr engines so goodness knows what went on there.


With regards to the camshaft caps, you could always fit standard camshaft oil seals.

Somebody may be able to save me some time
 

I was about to refit the acoustic cover on the engine after replacing timing belts ets. When underneath the throttle part of the upper inlet manifold. I spied a lone free female plug with 3 sockets perhaps in search of a male with 3 pins. Does anyone know what this free socket might be before I start dismantling again.The car has cruise control but no traction control. Perhaps it is the lead to/from the crankshaft sensor. Or it could be a lead that is surplus to requirements.
My wife tells me that wandering lone females are dangerous but I thought they were fair game!

Fred