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D7E 48A compression release

texaschad25 · 2019-02-27 19:07

My D7E 48A seems to be going thru starters at a pretty fast rate, and I was asked if it has a compression release. Can anyone answer this for me, and if so, where in the heck is it located? It has the pony motor replacement starer. Thanks!

Replies18
  1. #1kshansen2019-02-27 19:57

    Dang I tried SIS and not finding anything on a 48A. That said if the engine originally had a pony motor I would expect that it did have a compression release at one time. Never sure what might have been removed during the conversion. Hope someone who is more familiar with the D7E 48A will chime in. If I was there I probably could find it but trying to guess from this distance is not going to help!

  2. #2wrwtexan2019-02-27 20:03

    As that is a 4 hole version of the D342 in a D8H, wouldn't the release lever be at the bottom right of the dash/firewall as it is on my 46A 8H?

  3. #3RZucker2019-02-27 20:22

    Which part of the starter is being eaten? The drive? Unless the ring gear on the flywheel has been changed to a standard electric drive style, the conversion starters required a special pinion gear on the starter. I worked with a couple of old D9D's that were converted with standard electric start ring gears and 50MT starters, comp releases were disabled so nobody wasted batteries spinning the engines for basically no reason. they fired up easily in cold weather with a sniff of ether.

  4. #4Bluox2019-02-27 20:25

    Do you have glow plugs and do they work? Bob

  5. #5wrwtexan2019-02-27 23:09

    RZucker; starting the old 8 I ran, I would dump compression, load it with a snort of ether, get it spinning fast as it would then drop the lever and off she'd go. It has the 50MT conversion on it after pony removal but it wouldn't get rolling without compression released. Was the comp lever disabled for 'drivers' instead of operators ?

  6. #6RZucker2019-02-27 23:23

    I'm not exactly sure, there was no release lever and no glow plugs but those old D353's would light right off even down to 40 degrees without ether. They spun over pretty well. The stub shaft of the comp release was still showing out the rear of the block and the hole in the firewall was there. Was there a direct injection option for the 353?

  7. #7wrwtexan2019-02-27 23:31

    352? this old beast still had the fuel tank for the pony and no glow plugs so I would assume so. It's an early 8 (46A4560) so may have been before them.

  8. #8RZucker2019-02-27 23:54

    My bad, I was talking about the old D9D with the D353 engine. Yours would be the 342.

  9. #9Old Magnet2019-02-28 13:16

    Compression release lever/shaft should protrude through the lower RH dash. Even if lever is removed you should still see the stub shaft coming from the upper section of the engine block. What is failing with the starter? and is it a Delco 40MT, 42MTor 50MT starter?

  10. #10Mobiltech2019-03-01 07:21

    Is it a 12 or 24 volt starter. I thought when we converted them we switch everything over from 12 to 24 volt. If it has the wrong voltage starter it won’t last long.

  11. #11texaschad252019-03-01 10:30

    It's 24 volt, and I don't see aby thing coming out of the dash. I will look closer when I go down there later today. After the starter is rebuilt, it will spin and crank as normal. After several months, it will start lagging like it's a low voltage issue, but the batteries are hot. Since everything is made in China now, I'm wondering if it's cheap starter parts.

  12. #12Bluox2019-03-01 12:17

    How long do you have to crank it? Do you have glow plugs? Bob

  13. #13Mobiltech2019-03-01 13:33

    What size batteries do you have and are they wired in series ?

  14. #14epirbalex2019-03-01 17:16

    I have read on these pages that early D7E's had the D339 motor , same as the D7D , my release is on the side of the motor , one D7E I drove for a while had its leaver on the side as well , not sure what motor it had . You should be able to see the end of the shaft outside the end of the tappet cover and between the two covers . It may have had the shaft removed and the holes covered up .

  15. #15Dave Neubert2019-03-01 18:20

    do you have 0/2 cable and is the ground go to the starter or just the frame

  16. #16kshansen2019-03-01 18:54

    You say "after starter is rebuilt" did who ever rebuilt it say what had failed? Or did they just toss another starter at you and walk away? That is one reason I don't like just replacing a component with an exchange part unless the cause of the failure is well understood. You can get hooked in to a never ending loop of failed parts and never get to the root cause of the problem. I know often time is so important that "get her running" is the only thing that matters but that can set you up for repeat failures when you can least afford them.

  17. #17RZucker2019-03-01 20:53

    I'm betting on bad grounds in the system. The D9D's I worked with had both positive and negative run to the starter terminals with 2/0 cable. and both runs were les than 6'.

  18. #18Don k2019-03-02 11:30

    I had a D7 17a and it had the release on the RH side of the dash. Flip the lever up for release and lower it for compression. I had the pony motor. I lifted the lever to get the engine spinning then when I got oil pressure would lower it. I usually had to run it with compression for at least a minute before giving it fuel. If it was cold sometimes 2 minutes or more. I never used ether on it. If you don't have glow plugs I don't see how you could get it started with a battery and starter.