731 idle issues

[dude8710]

So i just picked up a 731 for cheap. has deutz 2cyl air cooled diesel engine. previous owner says there was a bad injector that caused a hole in a piston. got it home threw the charger on it and it fired right up. i have a couple of questions. obviously one is, can this really be running on only one cyl.? it idles pretty rough but not what i would expect with a shot piston. also it sounds like a valve is bent possibly? looking for any help i can get on this one guys. also if anyone knows where i could get a wiring harness for this would be great thanks.

 

[OldMachinist]

A compression tyest will tell you right away if there's a hole in a piston. Also if there's a hole you should be seeing a lot of blowby out of the crankcase vent.

 

[Tazza]

A compression tyest will tell you right away if there's a hole in a piston. Also if there's a hole you should be seeing a lot of blowby out of the crankcase vent.

They do idle and run a little rough, but they are an excellent engine.
If the injector is leaking it will burn a hole in the piston, i have seen it before. It wasn't right through, but it was a sizable chunk!
I agree with OM, do a compression test, see where you are at. Ensure the injectors are not leaking too. If there was a hole in it, you would get a lot of smoke and masses of blow-by.

 

[lecuyerb]

These engines are amazing. I have a 731 that ran ok. a little bit of vibration. It got worse over the next 500 or so hours. I tore the top end apart and one cyl had 3/8"-1/2" of play between the rod and crank. I could not believe the other cyl had enough compression to even start with the dead cyl but it did. It ran and started on half a crank till the play go to much and it just died one day. I had no idea there was even a problem sure it was down on powerbut I just did light stuff like trneching and material moving. I have since rebuilt the entire engine - very expensive even with cheap aftermarket parts - new cyls new crank/rods - everything all chinese or indian not sure and it was still like $2200. But other than getting the cyls and exhaust all lined it it is a dream now - I never plan to sell it. You can make the wiring harness if you get the manual of ebay or somewhere there is really only a few wires and it is very very simple.... Brian

 

[jigneshgn1]

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