# datsun 810 diesel problems



## pmogenhan (Dec 17, 2008)

I have a 1981 datsun 810 diesel and Im having problems with the electrical system. It takes a bit to get it started in cold weather, and it has to turn over quite a bit before it gets going. Recently it starts to turn over and then I lose power and it turns over slower and slower. I just replaced the battery and alternator and it still is having problems. I don't think its the starter either because when I first turn the key, it turns over no problem... its only after a couple of seconds that it starts to slow down.

Does anyone know what else it could be? I would rather not take it to a mechanic because the car is pretty rare, and I dont think anyone around here would know. I can do it myself as long as its not to heavy duty too. Thanks in advance!


----------



## bendantoni (Mar 9, 2009)

*Could be glowplugs*

Are you waiting for the glowplugs to warm up before starting? It could be the glow plugs, or maybe a compression problem. Try cycling the glow plugs a few times, then starting. If that doesn't work, I'd try spraying a little starting fluid into the air intake right before starting. Only do this once or sparingly, as continued use won't fix the problem and gets the motor addicted to the stuff. After the car is good and warm, will it start easily. If so then it's likely your glow plugs. 

Also make sure you have a fully charged battery, as it sounds like you're draining yours pretty regularly trying to start. When it runs is there smoke from the tailpipe, on startup? continues after startup? If it's smoking than it's likely a compression issue and probably needs a rebuild.

I'm not a mechanic at all, and this could be wrong, but this is what I've gathered from diesel mechanics. I have an 810 diesel and I LOVE it! It's worth and engined rebuild even if it needs it. Where are you located?


----------



## smj999smj (Jan 1, 2006)

I agree...diesel engines fire due to spontaneous combustion...as air compresses, it gets hot, fuel is added and the heat ignites the fuel.. Glow plugs help warm up the air to make starting easier. Glow plugs could be the problem...or any part of the glow plug system. Low compression could also cause this, as well.

Making sure you have the correct battery and that it's fully charged is important, too. IIRC, your 810 took a group 27 battery like most of the diesel equipped Nissans. Getting the engine up to proper cranking speed is important as it will make the compressed air hotter. Fuel quality and pressure are also issues to consider. A service manual would come in handy.

Don't overlook the obvious: Make sure all your fuses are good!


----------

