1964 806 Timing.... Allen in NE?

I posted this question several months ago and no one seemed to know the answer. Here goes again - My 806 has an after market M&W turbo on it. Needs a shot of ether for anything less than 60 degrees or so. The timing for a natural aspired diesel 806 is 8 degrees BTDC, per owners manual. Mine is set at 6 degrees BTDC. Is this necessary because of the turbo? Would changing it back to 8 deg. possibly help with the hard starting? I know there are several other possible issues that play into it hard starting. But my main question is about the timing, if it is correct or not. Thanks, Dan Swanson

Sounds like the injector pump if your motor is tight with good comperssion. You do not have to change the timing having added a turbo. Someone thought it might get a little mower power out of it by bumping up the timing but not nessary just because you added a turbo to a 361 motor. Adding a turbo on thoes tractors, check your air filter more often because they get more dirt sucked in if they are the orignal filter. On one of my 806's I changed the air filter to one off a 856 diesel. Larger filter.

It may help but not likely. The 1206 used a smaller total degree of automatic advance at full throttle due to the turbo. So it depends on what your pump advance total is to make a determination as to where to put the static timing. Also the 856 used more advance than an 806 and when a lot of pumps are rebuilt they are rebuilt or replaced with 856 pumps so when put on an 806 you retard injection to that 6 degree setting to compensate for this. I guess what I am saying is , if it doesn't make it start any better by going to 8 degree static timing I would put it back to 6 for better full load performance. I don't have my service manual handy right now or I could look up the actual specs.

Good afternoon Alan. Spring is just around the corner. Right?

My 1206 would not start at any temperature or timing setting unless I gave it a shot of ether. I had the injector pump rebuilt and now it starts most all of the time without ether...and it runs much better.

The sad part of experience was the $$sss spent trying to rejuvenate the old pump. Marv

(quoted from post at 14:21:29 01/10/10) It may help but not likely. The 1206 used a smaller total degree of automatic advance at full throttle due to the turbo. So it depends on what your pump advance total is to make a determination as to where to put the static timing. Also the 856 used more advance than an 806 and when a lot of pumps are rebuilt they are rebuilt or replaced with 856 pumps so when put on an 806 you retard injection to that 6 degree setting to compensate for this. I guess what I am saying is , if it doesn't make it start any better by going to 8 degree static timing I would put it back to 6 for better full load performance. I don't have my service manual handy right now or I could look up the actual specs.

Click to expand...

Adding to what Pete 23 has said, the end of injection timing is more important than the start of injection. Combustion needs to be complete by about 10° after TDC. The timing marks in the pump mark the beginning of injection.

i have to agree with the rest. if the motor is tight then you need a new injection pump. did you put the turbo on it? how long has it been on? how are the piston rings? checking compression on the motor would be my first step....

casey in SD

Along with what Pete and owen said may i add that on a 806 hard starting can be due to valve recession due to normal ware and also valves out of adjustment , then there is the injectors are they cracking at the proper pressure or are the dribbling When and 806 is wright and i mean wright they will start without either down to 0 and below. . But when they have had a steady diet of either to light them god only knows what is wrong . And like the one guy said a compression test will tell some . As either can knock the rings out and if the top rings are broken then you will be down on compression .I have done many 806 diesels and when they come out rebuilt they start like they did when new but myself i do get a bit carried away on my work and when i do one i do everything and nothing is left to do on a major overhaul . They are line bored and the cylinder bore is done off the centerline of the crank the head is done to spec. and valve protrusion is dead on the pump is done by a good friend that was also a I H mechanic and turned to doing injection work and he does the pump and injectors for me and they are dead on the first time . So with out myself , Pete or Owen looking at and checking this tractor ourself's we are all shooting in the dark . we try our best to give good advice and help . BUT there is no majic pill that will fix it if there is problems that we do not know about . So it may just take a pump rebuild or it may take a total overhaul and i will say this to you , a D361 is not the engine for a novice to rebuild and you need to know all the quarks of this engine or you could spend a bunch of money and had it come unglued in the first fifty hours and scrap the whole thig as i have seen this way to many times where guys did not want to pay to have it done and tryed them selfs only to scrap a block and crank and one guy i know did not lean the first time and scrapped five blocks and cranks before he gave up and had me do it . Would have been a lot cheeper to pay me the first time around .

when I bought it a year ago from the father in law. He bought it back in 90 - 91 from a guy that used as a back up to a 1370 Case. It was hard starting back then too. It does use/leak (rear main seal)oil when I put a good load on it. About 1 qt in a day. Thats is what it used back when the FIL first bought it. Sounds like if I want to get the the root of it I need to find me a good mechanic/shop. Thanks for all the help!! Dan