I am having a starter issue with my 1992 5.7l engine. It was having starting problems (slow to turnover and no start) when it got to operating temp. Checked the battery(new) then the grounds. No help. Then I replaced the starter. Still know help. Thought the starter was overheating, but check the temp on it and is was around 150 degrees. That should be within its ops range. I would like to try a gear reduction starter from a diesel 6.2l. but not sure it will fit the block. Has anyone tried that?
Nothing on google search.
Thanks

 

Can check the voltage drop across the ground and positive cables. Just a quick thought in passing.

 

How old are your cables? They may look good but have too much resistance to carry the current load. Going to another type of starter is not the fix to your problem. I had a cable once that looked perfect, until I started stripping back insulation and found at least a foot of green corroded copper. That was our 93 Suburban

 

You will need a vom that can do min max.

 

I am getting a voltage drop of about 2 to 3 volts when it is hot and will not start. I used a new ground strap directly from the battery to the block. The pos cable is fairly new and it goes directly to the starter. I replaced some of the ground straps on the frame to body and body to block. It could be because it is a low priced O'rellly's starter, but it is new and the one I took off was new.
Replacing the starter with a diesel engine starter is masking the problem, but, right now, I need something that will start. Can't take it anywhere .The engine was recently rebuilt by an unknown re-builder. There may be something going on there when it heats up.
I am trying to find out if the diesel starter will fit before I buy one and give it a try.

 

Well, a trip to O'Reilly's answered my question. The 6.2L Diesel starter will not fit the 1992 5.7L small block. I may go with an aftermarket one and keep looking for the problem.

 

Most of the time the reason you have a slow or no start on a 5.7L ( I have One) is a bad starter, bad ground cables, or bad positive battery cable. Looks like you have already checked or replaced them at some time so the next thing I would check is your timing. I assume that you don't know the history on this truck so I would check the timing next to make sure that is not the problem. The previous owner might of removed the distributer for any reason and did not reset the timing on it. 12 degrees BTDC should get you in the operating zone. If you want to try a new starter to get more cranking power, you can try a high-torque starter from summit racing. The one in my truck is from O'Reilly and it cranks the 5.7L engine just fine. I bought this one about 8 years ago and still going strong, ( I better knock on wood) . Hope this helps.

 

Is this being measured at the battery, across one of the cables, or the starter? If measured at the battery, perform drop testing on the positive cable.

Remember that a part being new does not necessarily mean it’s good. A volt meter is more than sufficient to determine the cause.

Are you using a side post battery? If so, make absolutely certain the bolts are tight - they are notorious for stripping threads and not maintaining adequate contact between the cables and battery. If you can rock the cable side to side with the bolt tight, the bolt isn’t tight enough.

Remove the insulation sleeve from the terminals and replace the bolts with a 3/8x16 hex bolt that’s 1” or 1.25” long. Thread a nut onto the bolt, then thread the bolt into the battery and use the nut to tighten the cable down.

Apply some kind of protectant to the terminals - petroleum jelly, dielectric grease, aerosol battery protector, or spray paint will work.