Allis 7020 Cold Start Issue/Engine Health?

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   I could use some advice on my 7020.  My issue is that it refuses to start cold
(tested in 50F shop).  Background is that
this tractor has an engine transplanted out of M2 combine that I moved the
intercooler parts over from the 7020 engine.·        
The injection pump and injectors were rebuilt within
the last 90 days.

·        
In swapping over the hardware from the original
engine, I did pull the cam to replace the front plate…and therefore I reset the
tappets.

·        
The starter and batteries seem to spin the
engine fast enough.

·        
In trying to start it cold, I tried it at ¼ throttle
and full throttle.  Neither yielded success.

·        
Using the glow plug for 60 seconds as a starting
aid does not help.   The intake housing
does get warm during its’ use, so I think the glow plug is working.

·        
If I plug it in and allow the block to get to
80F, it will start.

·        
I measured compression with all injectors out
using cranking speed and a cold engine. The cylinders range 200 to 210 psi
across the 6 cylinders.

o  
This evenness leads me to believe I don’t have
one or two dead cylinders.

·        
I measured compression after letting the tractor
get up to a running temperature of 140F. 
I then pulled #6 injector, installed compression tester and then
restarted it running at idle (750-800 rpm). 
This yielded a compression of 350 psi.

o  
This above test matches what I found in a 185
Service Manual…it states under similar circumstances, a healthy psi is 500.  My 7020 Service Manual offers no criteria for
a compression test.   I noted from the
parts book that the piston from a 185 to a 7020 is a different part number so I
don’t know if I can use the 185 spec.

·        
When running, the engine has near zero blow by
out of the valve cover.   This makes me
believe the engine isn’t shot.  Also, I
can run it down the road in high gear and it seems to have plenty of
power.  I wish I had access to a dyno to
measure actual horsepower.

What are people’s thoughts on what my issue is?   Has anyone ran a compression test on a healthy 649/301 turbocharged engine?

Edited by nowaktj - 6 hours 60 minutes ago at 10:38am

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nowaktj Members Profile Send Private Message Find Members Posts Add to Buddy List Orange Level Joined: 13 Dec 2009 Location: Elk River, MN Points: 738	Post Options Post Reply Quote nowaktj Report Post Thanks(0) Quote Reply Topic: Allis 7020 Cold Start Issue/Engine Health? Posted: 9 hours 36 minutes ago at 8:02am
	I could use some advice on my 7020. My issue is that it refuses to start cold (tested in 50F shop). Background is that this tractor has an engine transplanted out of M2 combine that I moved the intercooler parts over from the 7020 engine. · The injection pump and injectors were rebuilt within the last 90 days. · In swapping over the hardware from the original engine, I did pull the cam to replace the front plate…and therefore I reset the tappets. · The starter and batteries seem to spin the engine fast enough. · In trying to start it cold, I tried it at ¼ throttle and full throttle. Neither yielded success. · Using the glow plug for 60 seconds as a starting aid does not help. The intake housing does get warm during its’ use, so I think the glow plug is working. · If I plug it in and allow the block to get to 80F, it will start. · I measured compression with all injectors out using cranking speed and a cold engine. The cylinders range 200 to 210 psi across the 6 cylinders. o This evenness leads me to believe I don’t have one or two dead cylinders. · I measured compression after letting the tractor get up to a running temperature of 140F. I then pulled #6 injector, installed compression tester and then restarted it running at idle (750-800 rpm). This yielded a compression of 350 psi. o This above test matches what I found in a 185 Service Manual…it states under similar circumstances, a healthy psi is 500. My 7020 Service Manual offers no criteria for a compression test. I noted from the parts book that the piston from a 185 to a 7020 is a different part number so I don’t know if I can use the 185 spec. · When running, the engine has near zero blow by out of the valve cover. This makes me believe the engine isn’t shot. Also, I can run it down the road in high gear and it seems to have plenty of power. I wish I had access to a dyno to measure actual horsepower. What are people’s thoughts on what my issue is? Has anyone ran a compression test on a healthy 649/301 turbocharged engine? Edited by nowaktj - 6 hours 60 minutes ago at 10:38am
	D19D, D17D, WD, WC, Snobee, #83 Plow, SC Blade, 14' disk, 400 series planter, B , Terra Tiger, M Dozer w/Baker Blade, TL-12, 42S Grader, G

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Mikez Members Profile Send Private Message Find Members Posts Add to Buddy List Orange Level Access Joined: 16 Jan 2013 Location: Usa Points: 8929	Post Options Post Reply Quote Mikez Report Post Thanks(0) Quote Reply Posted: 9 hours 10 minutes ago at 8:28am
	Who put injection pump in. Maybe not timed correctly.

nowaktj Members Profile Send Private Message Find Members Posts Add to Buddy List Orange Level Joined: 13 Dec 2009 Location: Elk River, MN Points: 738	Post Options Post Reply Quote nowaktj Report Post Thanks(0) Quote Reply Posted: 9 hours 4 minutes ago at 8:34am
	Forgot to add detail about timing. I have double checked and the lines match up perfectly for 18 degrees BTDC. The dampener mark could be off, so I moved the pump gear back 1 tooth and forward 1 tooth and it did not run as well.
	D19D, D17D, WD, WC, Snobee, #83 Plow, SC Blade, 14' disk, 400 series planter, B , Terra Tiger, M Dozer w/Baker Blade, TL-12, 42S Grader, G

DrAllis Members Profile Send Private Message Find Members Posts Add to Buddy List Orange Level Access Joined: 12 Sep 2009 Points: 22855	Post Options Post Reply Quote DrAllis Report Post Thanks(0) Quote Reply Posted: 3 hours 52 minutes ago at 1:46pm
	So, how did it start cold when in a 50 degree F shop before you had injectors and injection pump gone thru ???? Set your pump timing at 16 degrees BTDC and leave it there. Cranking compression with a known good compression tester should be over 300 PSI with all injectors removed. Running on one cylinder at 700 RPM should yield you 400 psi or a little better. So, you either have a real problem or you have a compression tester that isn't giving you correct numbers. What brand starter does it have?? A LUCAS ?? they are known for slow cranking speed, regardless of what you think of the cranking speed. I assume this engine has the DM-4 style injection pump?? and that would have 15 to 1 compression pistons. LEAVE THROTTLE AT A DEAD IDLE TO START. Edited by DrAllis - 3 hours 44 minutes ago at 1:54pm

injpumpEd Members Profile Send Private Message Find Members Posts Add to Buddy List Orange Level Access Joined: 13 Sep 2009 Location: Walnut IL Points: 5208	Post Options Post Reply Quote injpumpEd Report Post Thanks(0) Quote Reply Posted: 3 hours 8 minutes ago at 2:30pm
	200 psi is not enough to start a cold diesel engine. I always do compression tests with starter, not per Ac procedure of it running on the other 5 cylinders. You problem starting is at cranking speed, so that is the speed you need to check it as you did, and it proved to be a problem. Faster cranking speed will definitely raise the cranking compression pressure. I don't feel you have an engine problem as much as you have a slow cranking problem. Looks like a great application for an ether start and a gear reduction starter lol!
	210 "too hot to farm" puller, part of the "insane pumpkin posse". Owner of Guenther Heritage Diesel, specializing in fuel injection systems on heritage era tractors. stock rebuilds to all out pullers!