SM IE: Valve adjustment and suspension noise

25 November 2007 | Mechanical, SM IE

During September 2007, my mechanic can finally work on the car. The goal is to adjust the valves, replace the secondary timing chains and track and fix the annoying suspension noise I have for a long time now. It will be a good occasion to do an interesting diagnostic.

The valve adjustment brings a few comments: the valves actually needed adjustment, one camshaft was lose (the adjusting gear) and some cam bearings were lose also. This maintenance was needed!

The problem is that once the valve adjustment completed, the mechanic spent about 20 hours to search why the engine didn’t want to work anymore. After a lot of search and 2 weeks, he found that a ground wire in the injection wiring harness was defective. This defect caused the fuel pump to not work anymore.

smie_198

Dominique and Claude searching for the electrical defect

smie_199

The injection wiring harness is not very dependable

smie_200

A good cleaning has been done on the relays plate

smie_201

A good part of the ignition wiring and connections has been restored

The main conclusion is that the injection wiring harness is globally in bad shape. The main wiring harness is not very nice either. It’s worse than I thought. On the forum of the french SM Club, I’m told that a german electrician is manufacturing new wiring harnesses for the DS and SM. It’s a good opportunity, I order a new injection wiring harness, it will make this part of the electrical installation much more reliable.

Once this problem fixed, the mechanic works on the suspension noise. This one is a lot quicker. After a few greasing operations and an inspection of the ball pins supposed (by me) to be the cause of the problem, he discovers that the noise is due to lose suspension arm holders. A few bolts are so lose that they can be turned by hand ! That’s crazy. When I disassembled my other SM’s arms, it was very difficult as these bolts were tight and rusty, but on this car the same bolts are lose.

So it was a big step forward. The engine is working fine, I’m more confident now that valves and camshafts have been inspected and adjusted. The suspension noise finally disappeared, no more cracking noise like a wreck car. Finally, the electrical problem has been a good opportunity to do a maintenance on the electrical circuit and plan to replace the injection wiring harness.

The car is out of the garage early October, but winter is coming and I have to store the car soon, after using it for only 50 kilometers. See you next spring.