73-87chevytrucks.com
73-87 Chevy _ GMC Trucks => Engine/Drivetrain => Topic started by: Joec123able on December 05, 2018, 07:51:48 PM
-
This truck has me at my wits end lately. Pulled intake to replace gaskets. Had to pull distributer and had problems getting that back in right. Got it in running and put a timing light on it and timed it to 4 degrees advanced idling. Then my starter started grinding. Piece of the ear is cracked off the block so I bought a starter that uses all three bolt holes instead of just the two offset. Now it still doing the same thing. If I unplug the ignition it will spin over all day, but once I plug the ignition back in some times it will start smooth and others it will grind. The distance between the armature shaft and the flex plate/flywheel is slightly under 1/8th inch so I’ll add a shim to get it about 1/8th inch otherwise idk what else to do...
-
Why would it turn over just fine with no spark (still compression) then grind sometimes when spark is put back? Has to be timing still doesn’t it?
-
im thinking you need to do the timing and start with finding TDC. personally i would run 14°-16° with the advance unplugged
-
im thinking you need to do the timing and start with finding TDC. personally i would run 14°-16° with the advance unplugged
Well if it’s “kicking back” at 4 degrees advanced, wouldn’t more advance put more strain on the starter? I guess I’ll check and see if maybe the balancer or tab are not actually accurate.
-
Don't assume that the timing marks are right. Unless you have verified the stationary tab is correct and that you have the right dampener and that the outer ring has not walked on the inner ring your timing may be off. After many years parts may have been changed. GM used a lot of different harmonic balancers during the years and were the marks were located at different spots. I have worked on a lot of these engines since the early 70s and run into a lot of variations. Also I would double check the firing order just in case one of the wires on the dist cap got moved. That will cause a kickback.
-
you would think more advance would hurt it but like mike stated, if your 4°s and your having issues then something isnt right with the timing either mechanical error or human, but something doesnt sound right. this is why i stated you need to find TDC, this will get you a baseline and tell you if your timing marks do or don't line up
-
Got piston one to TDC and checked the mark, it’s exactly at 0 at TDC and the firing order Looks correct.
-
Are you timing off the driver side front cylinder - left bank odd number cylinders, right bank even number cylinders?
-
Are you timing off the driver side front cylinder - left bank odd number cylinders, right bank even number cylinders?
Yep front driver first cylinder. 1-3-5-7 down the driver side of the engine and 2-4-6-8 down the passenger side from front to back. I just took a video and it is without a doubt kicking back on the starter. Time to pull the distibuter again cus something obviously is wrong there.
-
Are you timing off the driver side front cylinder - left bank odd number cylinders, right bank even number cylinders?
after you verify that will it start at TDC?
-
Are you timing off the driver side front cylinder - left bank odd number cylinders, right bank even number cylinders?
after you verify that will it start at TDC?
It will start it just kicks back. Onevstart it will fire no problem, the next it will bog the starter and kick back. Like I said, I took a video while I turned it over and it’s definitely fighting the starter
-
With the timing marks at TDCC, pop the distributor cap and look at where the rotor is pointing. Is it landing between distributor cap towers or pointing at #1?
-
Ignition Timing for First-Generation GM V-8 Engines (http://forum.73-87chevytrucks.com/smforum/index.php?topic=32085.0) Ignition timing, including base timing, total timing, mechanical advance, and vacuum advance
-
Well I’m starting to think it may actually be the carb that’s part of the problem. It’s not wanting to run very good unless the timings way advanced and when i Retard it it starts bogging and if I shut it off it diesels really bad
-
know on my mud truck i had a similar issue but after fixing a vacuum leak and timing to 16° she runs like a champ now.
-
I just cannnot figure this piece of junk out. The starter was working fine before I pulled the intake and now nothing but problems since. Put new starter and same thing. I’ve checked every part of the ignition a billion times. I’ve changed and adjusted the timing every which way possible, put a new cap and rotor on. Checked for vacuum leaks, there’s none. I’ve shimmed the new starter up and down every which way, it’s still chinging on the flex plate. I’m just so tired of this thing now and idk what to do from here.
-
Here’s a video of what’s its doing. First two cranks are with the distributor unplugged then plugged in after. Maybe y’all can figure something out of it.
https://youtu.be/2BSAv_JzCCA
-
Finally figured it out. New starter has 11 teeth, original has 9
-
Got to hand it to you for hanging in there man!
When I watched the video I wondered why the starter extension housing was missing.
Where did you get that pig?
-
Got to hand it to you for hanging in there man!
When I watched the video I wondered why the starter extension housing was missing.
Where did you get that pig?
It’s a ”prostarter” gear reduction starter. It’s about a 1/3rd of the size and weight of The original And puts out more power. I bought it because it uses all three mounting holes in the block instead of the two but guess I have to put the old giant style back in.
-
Wow, didn't know they existed! Don't they make one with the correct amount of teeth?
I'm all for lightening my heavy truck.
-
its been a while but someone on here had a similar problem about breaking the block for the bolt. cant remember how they fixed it (should be able to find it using "search")but ive seen people weld a stud in place of the bolt and use a nut to tighten the starter in place
-
its been a while but someone on here had a similar problem about breaking the block for the bolt. cant remember how they fixed it (should be able to find it using "search")but ive seen people weld a stud in place of the bolt and use a nut to tighten the starter in place
I have the old style two bolt starter back on and working good. Mines not completely broken off, just a chip taken out of it but still functional. I got the starter mounted to the exact specs it’s supoosed to be and also added the brace on the back that bolts to the block. Working awesome now. Took a lot of work.
-
Wow, didn't know they existed! Don't they make one with the correct amount of teeth?
I'm all for lightening my heavy truck.
Go on jegs.com and take a look at what they have. Not sure if they sell the smaller style with the correct pinion gear or not. It’s a very well built starter but oh well, I’ll settle with the gigantic old style for a while.