Clunk but doesn't Always turn over

[Chevybrit]

Hey All
Had a look at the wiring diagram and some of the older threads but just wonder if someone had experience with this exactly
When I turn to start i get the solenoid clunk and often it cranks but as frequently it doesn't

Its Had the doghead relay mod
i've checked the grounding and cleaned them

could it be the solenoid and is there a best replacement ??

Thanks chaps

 

[cucvrus]

Could be the starter. Have you had that down and looked at lately?

 

[doghead]

Put your eyes on your starter.

Is it tight?

Does it have the support?

Are all your connections good?

Are both batteries fully charged?

How long has this been going on?

 

[Chevybrit]

Been going on I guess at least 9 months (since I bought it / so could be longer) It would do it maybe 1 in 20 times i turned it over.
Turn key .. would clunk
Turn key off try again and would turn over and start

Lately about 1 in 5 times.

Freshened up the battery ground wire from batteries to the body.
Charged and load tested both batteries (good)

Will check the support and pull the starter off next

 

[m1008chevy]

I had this happen and it turned out to be the starter solenoid. You could try a voltage drop test between the positive terminal and signal terminal on the starter. If the voltage drop is more than 0.2 volts your solenoid is the culprit. This can be done by disconnecting the power going to the injection pump, and having someone crank while you probe both the terminals on the starter. Be careful with the moving parts while its cranking.

 

[Chevybrit]

Thanks for the response so far gents ..
I pulled the starter off this morning to take a look


First of all it was missing the bracket... it was tight but no bracket there ..
Q: The batteries are in Parallel so its had the 12v conversion .. this is obviously a 12v starter SO will the bracket fit ?

I saw on a different thread that these brackets could be had from amazon

https://www.amazon.com/dp/B00GV77H2U/_encoding=UTF8?coliid=IXBDWNEGWUCBD&colid=2JFQ0SJUHM6WP

But in the TM the shape is a kinked bracket..?

The starter and solenoid appear to be fairly recent poss the last PO... i know that doesn't prove anything but it was probably done when the conversion took place.



All connections were pretty clean and tight .. will do a drop volt test next ala m1108chevy suggestion above ...

 

[Chevybrit]

BTW
I did search the starter and it came up as a good replacement for the 6.2's i found quite a few links to Hummer threads... any comments on these?

 

[cucvrus]

The bracket will fit. Voltage matters nothing for the bracket. Both starters should be checked out and thoroughly gone over before you put any effort into installing them and saying that's not the problem. It is a process of elimination with good parts. Or just keep guessing and do more work and change more parts then needed. But yes get the bracket. It is mandatory. Good Luck. Report back.

 

[Chevybrit]

Took the starter apart, the brushes looked good and no obvious damage, plenty of life in them. When I removed the solenoid the small stud for the signal wire dropped inside the unit
it took me the next 2hrs to de-soldier the tab and to prise the top off it to get it out. Once it was all back together I cleaned all the contacts and re-installed it.
Other than the bracket issue, it has cranked every time I tried it .. so far about 15 times without a hicup .. it also spins the motor over a little quicker.
So far so good
Will report back in after a week or so ... My little girl is due tomorrow so who knows when I actually will

 

[Chevybrit]

Everything has been great with the starter .... its been used as my Daily for some months so i must have cranked it over hundreds of times now and not one problem .. the bracket was a mega pain and the best way was to fit to the starter loosely before offering the starter into its final position... I used a long 3/8 bar and swivel head socket for the top bolt.