Prechamber and threaded ring threads
 

I am considering buying or making a prechamber puller and prechamber threaded ring removal tool for OM621 and OM617 engines. From previous posts on this site

http://www.peachparts.com/shopforum/diesel-discussion/58446-300-5cyl-homemade-prechamber-puller.html?highlight=prechamber+tool

it has been stated that the prechamber threads are M22x1, which are the same as some Nissan half shafts and also some bicycle crank pullers/pushers.

Does anyone know what size and pitch the threads are inside the threaded ring, where the injector screws into? Does anyone have a cheap source for factory made tools? The cheapest I found is $40 to $50 for the puller and $80 to $90 for the ring tool. And, can anyone confirm that the OM621 engines from the 1960's use the same tools as the OM616 and OM617 from the 1970's and 1980's? Thanks.

The eBay and Tool seller Zdmak has a the puller tool and the claim it works on 1967-1999 engines- 601, 602, 603, 604, 605, 606, 615, 616 & 617
I bought a used puller on eBay and was suprised to find that it needed a metric adapter in order for me to use it on my Slide Hammer. After checking I found that the internal threads on some of the tools are metric threads and some have american threads. If you end up buying besure to check so you get the one you want.


The Ring removal tool is being advertised as working on OM615, 616 & 617.


I found the Injector thread size buy looking up the Compression Tester Adapter (that goes into the Injector hole) and they give the thread size for that. It said 24mm x 2.
This forum has a tool rental section.

I rent the ring tool.

The puller I made from the crank puller works as advertised, 5lb or greater slide a must.

If you tell what City you are in maybe one of the local Members has what you need to lend.

Thanks all for the input and offers to loan/rent the tools. I own several diesels and these are tools that I would like to add to my toolbox permanently. I think I have a bad prechamber in one of my cars (misses on one cylinder when cold but runs great when at operating temperature) and have decided to buy/make tools rather than use the old hammer and punch on the ring as I did before when one went bad. Made a crude prechamber puller back then too, but it really never fit well and really messes up the prechamber threads if you are trying to reuse the chamber. Since I am a cheapskate, won't use them all the time, and have access to a machine shop and materials, I should be able to make them for a lot less then those tool places want. Just need the thread sizes so I can buy whatever dies I need (which is still a lot less then buying the tools).

Here is a pic of the used tool I bought to remove the rings. Notice it is not like the ones you normally see. It is made by Wilbar.
Anyway I measured the business end of the tool and the:
od= 1-7/32"
id= 61/64"
Tab Width= 19/64"
Tab Depth= 3/32" (I think they should have made them a little longer)

I tought about making my own tools also but the 22mm and 24mm bolts were not avaliable at all locally and I could not find the 24mm one on the internet.
Even the 22mm one was too expensive if I bought 1 bolt and had it shipped to me.
I lucked out and got a good price on the used tools (it also came with the puller). (I have a metal cutting Lathe and Milling Machine in my garage.)