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01.03.2005

The engine (the runner, or Renault if you like..)

For the time beeing an old Renault RC8D is installed as engine. We do not know very much about these engines, and that can be a challenge. Since Renault put an end to their marine division in 1982 and sold out to Nanni, not much information can be obtained. But it still works for us, and I hope it will for a few years yet.

The alternator did not work when we bought the boat. It was as simple as the lack of a fuse! We put a 15A fuse in in front of the external regulator, and then all was fine. You can get a glimpse of the motor in the picture below.

We do not plan to do very much with this engine. Change of filters and oil, inspection for leaks (there is diesel in the bilgewater) change of alternator and waterpump-belt. We will change the impeller also. It could need a complete overhault, but we are afraid it will not pay off. Ordinary maintanance will have to do. Valve clearance will be checked and adjusted.

After searching the web for information concerning this engine, we were lucky to get a tip from France. The engine is based upon a Hatz diesel, as the BMW D7. This was good news, as spare parts seems to be easily availible. In Scandinavia a "German engine" sounds a lot better than a French engine. Weird really, since among others, Ford tends to use Peugeot diesel engines for their automotive division. I kbnow also that Jeep (when AMC) used Renault diesel.

After 3 seasons with the engine, it is now clear that we must do a larger overhaul. There are leaks, loss of power, and black smoke when we push it. So we went to work, loosened all parts, disconnected the wiring and pulled the engine out of the boat. It went quite smoothly really. Even though this iron block weighs 83 kilo... We brought it back home for a major overhaul. Pictures and progress will be put on the web.
The plan is to clean up all the mess, give a new coat of paint and replace what need to be replaced. We might use a light color to make inspection of leaks easier.We will also take a closer look at the fastenings of the generator and the raw-water pump. The pump is not the original, but a Johnson pump. No need to replace that, it's good quality.

We must have a close look at the injector and the injection pump. The engine has created some heavy smoke under preassure, and the injector is probably the cause. I've never done this before, so I'm a bit concerned. Maybe we should take the engine to a Dieselgarage. Pictures will follow.
No pictures yet... But a lot of work has been done. We opened the cylinder and cleaned all out. We found that the culinder has been somehow modified. There was a shim in the bottom of the cylinder that was not oiginal. And it was made of copper. I have measured it to 0.7mm. We have now replaced it with new shims at a total og 0.67mm made of brass and shims-steel. Copper is not a good option because of its caracteristics. When heated, copper turns soft and can be hammered down in thickness. This will cause leaks.

The cylinder with the head is now assembled, and we have measured the compression to 19:1. Both according to given spec and even calculated spec, this is perfect. Next thing to do is to start the engine to see if everything is ok. We believe everything is ok now, but there is a small concern weather we got the allignment of the crankshaft and the camshaft pinions right.

We have got the injector back also. The needle was not good, so the whole injector is replaced. This will help a lot (hopefully).