lift pump 240 vs 300 - PeachParts Mercedes-Benz Forum

surveyguy · #1 10-12-2011, 11:06 AM

will a lift pump from a 300 work on a 240?

Thanks.

kerry · #2 10-12-2011, 11:22 AM

I'm guessing yes, but you could look up the part numbers here on Fastlane to see if they are the same.

charmalu · #3 10-12-2011, 11:34 AM

Fast lane didn`t show the lift pump when I first looked up a 240. but in another Catalog it shows both, the price is $17 difference and the part# is different by one #.

they look the same, and I would guess they would interchange. maybe the pressure valve/spring is different?

Charlie

tangofox007 · #4 10-12-2011, 11:37 AM

Quote:

Originally Posted by surveyguy

will a lift pump from a 300 work on a 240?

Some 300 pumps won't even work on other 300's. Perhaps you could be a little more specific about the models in question.

Stevo · #5 10-12-2011, 11:40 AM

I remember reading a post way back when, indicating the pressure was higher for the 617 pump.

surveyguy · #6 10-12-2011, 11:53 AM

I tried to do that Charlie, I wasn't successfull in even finding either pump available, ha!

ok, my 240D is in my signature for "being more specific" and the 300 is in a junk yard that i know of so i'm not sure of the exact engine.

I found a guy that would send me a used pump for $50 and i was going to call a yard that I know has a 300. Am i barking up the right tree? before i asked and didn't get any response, so since this thread already has 4 replies which i'm very grateful for, let me re-ask:

my lift pump on my 240 is kaput. what should i do? (buy reman $150? rebuild it? buy used?) I've been told by someone i trust and honor, to just get one from a yard because they rarely go out (and more reasons). Is $50 a good going price i ask? When i operate the primer, it does work so i dont think it's the valves. it's just not pumping very much (i must get out every few miles and re-pump) and there is not even a drop through the return.

i appreciate this

Guy

kerry · #7 10-12-2011, 12:08 PM

************ shows a new one available thru special order for $168. A cheap electric pump would work as a substitute until the new one came in.

surveyguy · #8 10-12-2011, 12:14 PM

Kerry

i was thinking about an electric pump. I could ask them on that. I was envisioning one from a VW bug, but they're like $100 for a bosch, maybe my local (small mom-pops old parts store) has a generic elec. pump laying around.

I guess there's this one for instance, thing is, $50, i may as well put a used 240 in if the electric would be "temporary".

http://www.jcwhitney.com/micro-electric-diesel-fuel-pump/p2031585.jcwx?filterid=j1

$170 sheesh. decisions-decisions.

charmalu · #9 10-12-2011, 12:50 PM

There is a Lift Pump repair kit.

http://www.peachparts.com/shopforum/special-order-mercedes-parts/183451-om617-951-952-lift-pump-repair-kit-w126-120-300sd-w123-133-300d.html#post1461282

http://www.peachparts.com/shopforum/2159616-post48.html

http://www.peachparts.com/shopforum/2178915-post115.html

The thread where I got the info in in the upper right corner of those linked.

thinking that you have to get out every few miles and pump the primer, you might be sucking air in a rubber line. maybe at a clamp, or the hoss are just old and cracked?

the repair kit is much cheaper than buying a new pump.

Charlie

Stretch · #10 10-12-2011, 01:05 PM

I think you'll find that the fuel pumps / lift pumps on the non turbo 300Ds are about the same as the 240Ds.

For the sake of saving some money - even $50! You might find this thread of some use

http://www.peachparts.com/shopforum/diesel-discussion/294499-refreshing-fuel-pump-om617-european-spec-%96-non-turbo.html

I think this fuel pump is almost the same as this one that I've got attached to another spare non turbo IP

This fuel pump and IP combination is of an earlier type.

Biodiesel300TD · #11 10-12-2011, 01:14 PM

Guy there is a 240D in the G 'n' R lot in Albany. It's either a 77 or a 78, I think. I believe it still has a lift pump. I could make a quick run up there and see and/or grab it for you.

Stretch · #12 10-12-2011, 01:14 PM

If you check in the FSM chapter 07-145 (OM616 / non turbo OM617 W123 FSM) you'll see that the data in the FSM is pertinent for all of the following Bosch pumps

FP/K22M101 => MRSF pumps (Picture shown in linked thread)

FP/K22M7
FP/K22M3 => MW pumps (Picture shown in this thread)

FP/K22M13
FP/K22M14 => M pumps (These are the ones with the little air filter on top and their own separate lubrication system)

tangofox007 · #13 10-12-2011, 01:57 PM

Quote:

Originally Posted by surveyguy

ok, my 240D is in my signature for "being more specific" and the 300 is in a junk yard that i know of so i'm not sure of the exact engine.

In that case, an exact answer cannot be provided.

Quote:

Originally Posted by surveyguy

When i operate the primer, it does work so i dont think it's the valves. it's just not pumping very much (i must get out every few miles and re-pump) and there is not even a drop through the return.

It's very difficult to understand how operating the primer every few miles could possibly overcome any deficit in fuel supply.

surveyguy · #14 10-12-2011, 03:33 PM

correct, an exact answer could not be given with the data given, i just didn't know that. I learned by asking. Is this a reoccurring thing for you when others don't know everything? if the answer to my original question was "no" or "yes" then i would have asked it perfectly. My apologies for not knowing what i don't know.

re-priming re-pressurizes, gets the air out of the way, and re-fills the filter. The filter gets used to a point about an inch from the top. The pump is running , just very little. Maybe my pump was not told that it could only work perfectly or be 100% broken.

Thanks so much Army and Andrew !!!

barry123400 · #15 10-12-2011, 05:10 PM

As stated the lift pump off a non turbo 617 should be a direct replacement with higher output pressure. That way when the secondary filter starts to lose efficiency there is residual pressure reserve to overcome it better. Plus keep pressure up where it should be in the base of the injection pump.

The lower pressure lift pump on the 240d 616 engine is another reason the number one rod bearing wears out with no absolute proof. Actually both those lift pumps are economical and easy to rebuild.

As you eluded to the difference between the two pumps is the spring that determines the output pressure. The 617 spring in a 616 lift pump has to be better than the original. Although the original is fine as long as the fuel fllters etc are really kept on top of. Most probbly they are not in my opinion. This is less serious in a 617 engine.

All this said entrained air in the system alone should not be generated by the lift pump. Although by some strange way it may contribute I suppose. I personally would test the lift pump before diving in . A liquid dampened pressure gauge on its output deadheaded and a direct feed out of a can should produce 15 pounds pressure or better. Just a few pounds the lift pump needs a ten dollar rebuild kit.

Also if one were to submerge the output line into a container and watch to see if air is coming through in the form of bubbles. with the fuel itself is another test. There should be no air processed. Also watch the primary filter for a stream of air bubbles going through it. Air is not likely the lift pump but may be in some strange way again. It is not what I would immediatly suspect.

Although if the pump were indeed very very weak and the valves seating poorly in the lift pump maybe fuel could back drain I suppose. This should result in harder startups than normal after the car sits overnight as well perhaps.

Now if you have some form of wvo setup or are burning that as fuel all bets are off. The tired old lift pump besides contaminates may not be able to handle the higher visosity fuel. Thats why some I have examined have a booster pump near the fuel tank.