Home   Forum   Classifieds   Tech/DIY   News   Articles   Chat   Contact Us

617 Diesel Vacuum Pump - Caution!

Tech forum for DIY, repairs, restoration, problems, questions, etc... Post here get answers!
User avatar
Posts: 7227

617 Diesel Vacuum Pump - Caution!

Post#1 » Wed Jul 11, 2018 8:57 am

A short clip showing how vacuum pump internals can wear and fail. Even if the pump is working (pump in the video was) it could be close to causing a catastrophic danger to your engine as broken parts are scattered down your timing chain and into the oil pan. Rebuild kits DO NOT address these points of failure.

This applies to the 617, 617a and even the 602/603 and 602a/603a engines. Be informed!

video: https://photos.app.goo.gl/FNRF6jLZSG5tqCxz5
"The way you think is the way you live"

Posts: 1579

Re: 617 Diesel Vacuum Pump - Caution!

Post#2 » Wed Jul 11, 2018 10:42 am

Thanks for posting Vadim. I'll be checking mine.

User avatar
Posts: 1196

Re: 617 Diesel Vacuum Pump - Caution!

Post#3 » Wed Jul 11, 2018 11:56 am

Dude. I have to check mine aswell. Great video / post. Thanks!

User avatar
Posts: 219

Re: 617 Diesel Vacuum Pump - Caution!

Post#4 » Wed Jul 11, 2018 12:45 pm

Wow, this is pretty loose. How many miles this has been on engine?

I have also read about bearings in those vacuum pumps, another failure point, somewhere there was even suggestion to mount magnets beneath the pump housing to catch the balls.

Well, somewhat going off the rails but as OM617 turbos are hot topics currently…

When I took my two vacuum pumps apart, both had solid bearings and bushings, I thought long about replacing the bearings for one going to engine but didn’t chase it.

Eventually those old motors will fail one way or another, reasonable preventative maintenance is essential and also okay occasionally to poke some things deeper to catch something like above from happening but whether to rebuild those engines system by system or wholly… had I known what I know today ( :lol: ) I would have gone for swap from newer donor (OM605/6 or even OM612/3).

My OM617 story is that previous owner made the swap, then he drowned it on off-road competition, found another to replace and when he sold the vehicle I got the one with shorter rod as extra. The engine on car wasn’t great but moved the vehicle decently till one day half of second piston ditched the ride through cast iron wall. Mechanic said that out of five cylinders two were not working (as should), two were so-so, and one was good enough. We joked that this engine was from some taxi. Yet the G started on cold winters, saw some highway and fair bit of mud action. Also had no abnormal oil or fuel consumption, heavy smoke, noises or heating issues.

For those engines it is not the end of road for many years and miles when things are far from ideal.

Then two engines got rebuilt to one. Block and head work was done well: new pistons, chain, bearing, surfaces machined, crank grinded and balanced, valves lapped etc. And this part is still strong, after this rebuild engine has done roughly 45,000 km before whole vehicle went to ‘project’.

But for every accessory just best of two was chosen. And there lies the issues I am still dealing (what have been there since the engine rebuild and before). The IP was worn, they can be adjusted to certain degree but one point also need full rebuild; ok now I have a Bosch remanufactured pump, test guy was pretty impressed. Water pump housing leaked because corroded ends. Turbo worked but I was quite surprised when I took it apart, another thing needing full service. There were lot of oil leaks, some surfaces were damages from previous repair works, it just takes a small screwdriver mark to things not align up perfectly, on other places not right gasket were used. Some small bit and brackets missing. Turned out that oil filter had stuck valve etc.

In the end, going over every system, replacing every gasket, seal, hose, bearing and bushing, machining and matching all surfaces etc., this five figure Metric Motors offer in other OM617 rebuild topic seems reasonable price. But as those engines get older, some parts become unavailable: like valves in those vacuum pumps, or turbo parts. Least now the pistons are back. And option not going over every system means that something will fail one point. Last new cars with those engines were produced over 30 years ago.

Now, in this part of world, with 1000-1500€ it is possible to find Mercedes car with 130 or 145 KW diesel engine what might need a serious service but not every system rebuild. And it is good for many more rounds around planet. With this, keeping, meticulously maintaining and rebuilding OM617s does not make much sense, even with issues arising with swap. Of course I will drive and keep mine in order till it lasts but preserving history is for museums.

Still on frame and under deep cover of oil:

As it waits to put back on frame and all accessories attached:

1985 300 GD Turbo (Project)

User avatar
Posts: 7227

Re: 617 Diesel Vacuum Pump - Caution!

Post#5 » Wed Jul 11, 2018 12:55 pm

That is a beauty you have created! Thanks for the write up!

I have no idea how many miles were on that vacuum pump, but probably over 220K
"The way you think is the way you live"

Posts: 721

Re: 617 Diesel Vacuum Pump - Caution!

Post#6 » Wed Jul 11, 2018 1:14 pm

What about replacing the pump completely with an electric one such as this:https://www.summitracing.com/parts/sum-760152/overview/
1984 W460 280GE Cabrio

User avatar
G Nome
Posts: 3589

Re: 617 Diesel Vacuum Pump - Caution!

Post#7 » Wed Jul 11, 2018 1:17 pm

Thank you Vadim for posting a great head up video.


User avatar
Fernando BR
Posts: 1783

Re: 617 Diesel Vacuum Pump - Caution!

Post#8 » Wed Jul 11, 2018 3:18 pm

really nice video

User avatar
Posts: 502

Re: 617 Diesel Vacuum Pump - Caution!

Post#9 » Thu Jul 12, 2018 11:31 am

What seems to be the best source to acquire a sufficient rebuild kit? These aren't available new as a complete unit are they? Is the 617 and 603 the same pump? Also interested in an electric unit Ike goat suggested.

User avatar
Posts: 962

Re: 617 Diesel Vacuum Pump - Caution!

Post#10 » Thu Jul 12, 2018 11:54 am

burqueDOKA wrote:What seems to be the best source to acquire a sufficient rebuild kit? These aren't available new as a complete unit are they? Is the 617 and 603 the same pump? Also interested in an electric unit Ike goat suggested.

The 617's and 603's definitely use different style pumps. I replaced the pump on my 603 as a precaution years ago with an updated pump that should never give trouble. There is a picture of the updated 603 pump a few posts down on this thread http://www.peachparts.com/shopforum/die ... -pump.html

As for the 617 I am unsure of any updated pumps and have more research myself.
2015 ML250
1991 350SDL
1990 300SEL (Parts Car)
1982 300GD Cabrio (For Sale)

Return to “G Wagen Technical Forum”