primer pump assembly 617.952 - Page 2 - PeachParts Mercedes-Benz Forum

obiwanrazzy · #16 03-16-2007, 05:46 PM

Hey Nibiru,

The gasket is on the way, so I might as well wait and use the new one. I definately will try the lock-tight on the supply fitting (on the primer pump fitting too?). Have already replaced the short line, inline filter, and longer supply line. Cigar return line from the spin-on filter is all I have left to update (also on order).

Next in the great leak hunt might be the injectors themselves. There is just a little diesel "dampness" around most of them. Not sure if it's the injectors or the return lines coming off the injectors.. It doesn't seem like much has leaked there, however. No puddles. Do you think that might be a problem too?

obiwanrazzy · #17 03-24-2007, 02:18 PM

Take a look. I was definately loosing oil out of here (didn't realize the IP was bathed in oil). I'm thinking, hopefully, that this is the primary reason I've been getting ~11mpg lately. Time to order another part I guess.

Alastair · #18 03-24-2007, 03:16 PM

In the U.K. we have had ULSD (Called either City-Diesel or ULSD here) only stuff available for around 7 years.....

Most Injection-shops reported an increase in leaking fuel systems, as the ULSD can in some cases cause the older 'O' ring seals to shrink slightly, when the stuff went on widespread sale...

There was also anecdotal evidence of increased pump wear, and failures....

It does however, burn significantly cleaner than 'Full-Fat' diesel, and also does NOT give as many MPG OR Power as 'Proper Full-Fat' diesel either.....

nibiru · #19 03-24-2007, 06:15 PM

Howdy ObiWann:

Mine looked sort of the same - I am having trouble with this new ULSD we get on the west Coast now - One tank driving thru California north to Victoria and my ip on ford F350 Navistar has never been the same

Since you are where you are , mechanically work wise - change out the braided return lines - VW places usually have these size in stock for a decent price - just to be sure - the fuel could have leaked on the gasket of the primer pump - you never really know for sure -

I use the lightest loctite on all things now calling for a gasket sealer on these Mercedes - as its the only thing I am finding that can handle the vibration and the new fuel stuff

have you investigated additives to your tank due to this new fuel- ip's are expensive and a chore to change and adjust

in Germany folks just use salad oil in the tank and put a 10 or so litre of Dino in tank - cheaper and cars run great from what I hear - these are the new MB diesels

A qt of cheap new trans fluid per tank , b20 ....etc.. i am sure the list goes on and you will hear many oppinions

Also - another story I have heard is the new rubber tube , pipe , hose etc.. is supposed to be formulated to handle the new ULSD and bio - as the industry has prepared for this since late 97'ish- no need to hunt Viton or some of these expensive compounds - but again - I tell all - this is just what I have heard , read - please investigate for yourself and if so inclined , share what you find out

No doubt you'll get it all squared away better than you imagine

Cheers

obiwanrazzy · #20 03-24-2007, 06:51 PM

Hey Alastair, nibiru,

Actually I've only had the car for a short while. I've been putting B99 and/or B20 in it. The previous owner also was running Bio, but I'm not sure what blend. It could be the ULSD blended into the B20 but I really don't know... None of this would explain to me the broken assembly (notice the piece in my hand in the pic). I think it was mostly age/vibration. I did get a new gasket for where the assy meets the IP (I was hopeful that it was only a bad seal).

So a braided line to replace the one in the pic (goes to spin-on filter assembly)? Would it be terrible of me to just put a new rubber line there? Currently the line is part clear tube (from the primer assy) then trasitions to regular rubber (to the banjo bolt on the filter assy). Seems a little Frankenstien to me, but I wonder if there's a reason.

Something else I wonder: Do I need to worry about how/where the innards of the primer assy meet up with the innards of the IP? Or does it just go on?

nibiru · #21 03-24-2007, 09:23 PM

Howdy ObiWan:

Sorry - i was refering to the return lines - i thunk you had mentioned wetness at the seal ring / bottom of injector

If previous owner was running bio - goodly ...... but when did he change the return lines ( braided injector return lines ) those are cheap - maybe 10$ if that to replace - Rubber is fine as well - My feeling is as long as good quality and tight fit - I think those are 4mm id ( inner diametre) mid 80's - mid 90 chevy 6.2/6.5 use the same size

If using rubber - get from a place you KNOW carries diesel fuel line

Primer pump assembly has little play in it's seating ( just goes on ) - but as is mechanical spring in there - will seat properly once bolts are torqued- How I did mine( all without installing any of the fittings -- Holes covered of course ) was got the bolt's most easily thread by hand in first - right , bottom , left( closest to front of engine ) - tightened bottom , then right - you get it - not saying this is the CORRECT WAY , or the best way - just what I did - as that bottom mount bolt was a pain , then the left almost as bad- but you got it off so you know already - make sure all is as clean as possible , - dress the gasket if you like - you'll get many opinions here- I use HYLOMAR so I dress my gaskets

Say - how oily is the drivers side of the motor?

Cheers:

obiwanrazzy · #22 03-24-2007, 10:20 PM

Yes, those little nuts were a pain. I ended up cutting a 10mm box wrench in half (dremmel) so I could clear all of the obstructions.

Ah, yes the injector return lines were replaced with Vitron. PO had all of his work done just after he purchased the vehicle in Sept 06, so it's not been too long. Anyway, they all seem fine for now. Then again, there is that wetness at the injectors, so maybe they're not on tight enough. I'll investigate. I'm thinking for now that having an intact primer pump actually sealed to the IP should help a lot.

Yes, the driver side of the engine looks like it came out of the La Brea tar pits. I'm also sweating from the lower oil cooler hose, so it's pretty much covered with 15W40 under there. That engine mount is half disolved from fuel and oil as well. All of this is on my work list, of course. If only I could quit my day job, I might get it all done in a month of Sundays...

nibiru · #23 03-24-2007, 11:17 PM

Howdy obiwann:

Right on - i wonder about this Viton as i have read a few things that Viton actually is not that great for Bio - the regular rubber will outperform - Like I said you investigate and see what you come up with

As for the injectors - if they were loose you would know - not likely to leave fuel like that without a performance drop

I private for a few people - mostly Mercedes W123's - usually the oldtymers refuse to change the oil less than 6-7 thou - even if the oil has been in there for 6-7 months -
these diesels are sooty. Acidic the oil gets and micro metal shavings eat away at the seals and rubber - how is the area around your ac compressor and down the pass side engine - under the engine bay - like by the exhaust down pipe - usually these are the first areas of major problems

You'll get it all done in due time - addictive it is to turn your own wrench on these - i think you are beginning to find - and as warm weather prevails along with later sunsets - know where you'll be

I am in the process of installing bypass oil filters in all my diesels - either Motor Guards or Frantz- engines oil first , fuel filters next and tranny filters for the automatics-

Find a pick - n - pull or some variation of these near you - half price day if possible and get another Mercedes jack - makes things so much easier

cheers

obiwanrazzy · #24 03-24-2007, 11:47 PM

Passenger side seems okay, but it might just be that it hasn't caught my attention like the oil bath on the drivers side. I'll look when I'm under doing the cooler hose, oil change, pan gasket, etc... I see your point about a second Mercedes jack. I've a floor jack, should I be careful using it on this Mercedes frame?

By the way, I like your sig. Roy Batty. Now I'm goinna have to pull out Blade Runner after the kids go to be tonight.

obiwanrazzy · #25 04-12-2007, 10:41 AM

Update...

I botched the the replacement of the primer assembly somehow and was leaking oil quite profusely (much more than previous). Since I still had a long list of work to do and a short amount of patience left on the part of my wife... Took it in to an indie shop.

They re-did the assembly mount with a new gasket along with lower oil cooler hose, engine mounts and a bunch of suspension work (ball joint, idler arm).

So far so good on the leaking. I *think* the mileage is back up in the ~25mpg range. I've got a little drip hear and there in the head gasket and in the IP to engine gasket, but I think they might be tolerable for now.