806 Strarts hard

I have a Farmall 806 diesel with original everything. I bought the tractor from my grandfather and it always had a hard time to start. I replaced all battery cables, batteries and changed all filters.I don't use the tractor in the winter so cold weather starting is not an issue. The only way to get it styarted a lot of the time is with the dreaded either. Even then when it first starts it acts as though it is not firing on all cylinders. But give it a minute and it runs GREAT with no smoke. Any ideas would be great. Give me every option you can think of. And yes I know, get rid of the either.

I know nothing about diesels except the the 806 uses glow plugs--they may need replacing.

No glow plugs on an 806. Direct injection. The 706 with 282 has glow plugs. The 806 and 1206 with the D361 and DT361 repsectively are direct injection engines. The first thing you might want to check is your compression. If your compression is low you want to look at rings or valves. Second thing is your injector pump. It may need a rebuild. The injector pump would be the easiest to try first I suppose, but it really sounds like a compression issue to me.

Have you checked the valve lash lately? May not hurt to see what the gap is. Easier than getting into the injection pump.

Ok , here is the deal on your 806 problems.If a 806 will not start in cold weather or even worse in mild temps. then one it could be low compression , two the starter may not be turning it over fast enough and thus a low cranking speed even though you have sone all the usual stuff batterys and cables . next it could be that the injectors are not cracking at the correct breaking pressure and the tips may be worn or pluged and the spray pattern is bad. Could be that the injection pump is low on pressure at cranking speed , not knowing if it has a roosa master or the R D pump. Don't know how many hours are on your tractor or how it was kept up . Pump timing may be off a bit . IF the head was ever off for a valve job and they ground the valves to far into the seats then compression will be down and this is enough on the D361 to start making her hard to start . When a D361 is done correctly they will start down to 0 with out either and if they are really good even down lower . I have been around them since they first came out and worked on many . This engine is NOT for the novice everything MUST be BY THE BOOK or they are hard starters or they come a part in short order after rebuild.

MY FARMALL 806 DID THE SAME THING SINCE I GOT IT 3 YRS AGO. HAD TO USE ETHER EVERY TIME TO START IT NO MATTER WHAT THE TEMP.RD PUMP FLEW APART THIS SUMMER BAILING HAY. I PUT A ROOSA MASTER PUMP ON IT AND SOLVED ALL MY STARTING PROBLEMS.DONT NEED THE ETHER AID ANY MORE. CANT BE HAPPIER ABOUT THAT.

Yes, brain dead, sorry.

like all diesels they need to crank fast enough to build enough heat to fire the charge of fuel,check the cranking speed first

Chech your valve lash (0.012?) and the injector pump timing (adjustable by loosening the tow bolts in sloted holes, Roosamaster). These are the two most commone issues. Next would be the injectors. I have found Power Service diesel probucts help. My 504 would start missing under load. I used the silver bottle of additive at 2x strength through 2 tanks of fuel. No more missing.

Charles

NO THE VALVE LASH IS NOT .012 on a D361 engine This is a good was to put a valve thru a piston and ya never set the valves running . THE CORRECT VALVE LASH IS .013 on the intake and .025 on the EXHAUST on a warm engine and by warm i mean ROOM TEMP of 72 degrees or warmer. The D361 is not even close to your 504 engine .