Apparently, two (2) are spoken for.

Down to three (3).

As noted above, there will be a delay in shipping these. If you pay now, you are guaranteed one.

Thanks again !

Thanks Again .... all spoken for !

I'm not very damn happy with this forum right now; didn't ever get notification of any other post in this thread, until today!

If you build more, could you PLEASE PM me as I asked? Thanks.

I will try to remember ... not intentional ...

Pardon me for asking, but why would one want to increase the pressure when Mercedes gives a specific value range of pressures that the pump should see? It would seem that the risk of damage to the fuel system would be very real if you increased pressures beyond the factory specified 1.0-1.3 bar.

The manual says that if the pressure drops below 0.8 bar to simply remove the spring, stretch it to 27mm and then check the pressure. If it's not within the specified range the hollow bolt assembly should be replaced with a new one and/or the lift pump should be replaced or rebuilt.

After all, the new part from Mercedes (000 074 72 84) is only $27.00 list from any dealer, probably less from some.

Just wondering....seems like a rather dangerous thing to be doing, not to mention a possible waste of money...

People run 45 psi (3 bar) no problems. I stretched the spring so tight the return line has only the injector return fuel going through it. And that's after I "de-stretched" it :P Sorry to Greazzer for going beyond his springs intentions ;)

In addition to the "performance" aspect, there's also a service/functional aspect to using one of Greazzer's overflow valves. On the later vehicles (60x engines) the overflow valve has a fairly weak spring and a plastic element inside of it. When (not if) the plastic element warps or breaks, the fuel pressure in the fuel rack drops at low RPMs and the "check valve" function of the overflow valve is lost. The result is (or can be) rough idle, poor low-RPM power, or rough starts from cold when sat.

I had the latter issue with my SDL. A new overflow valve from the dealer with tax (or ordered online with postage) is roughly what Greazzer is charging for the older style valve that gives a positive seal and can be serviced in the future when it gums up or gets spring fatigue. Since I can't seem to find one of the valves to save my life, the choice to pay the dealer or Greazzer was a no-brainer. My car is much happier in the mornings, no more craptastic cold starts.

Mercedes did not design the fuel system. Nor did they produce it to the best of my knowledge. The designers of the system had concerns that perhaps have not proved to be justified. The minumin operational pressure has validity.


They did expect certain levels of maintenance that in general was never performed often if at all. They perhaps where also the first to produce a diesel fuel system with no water and sediment trap. At a time when this was far more important.


Increasing the base fuel pressure does result in better filling of the injection pumps elements. Producing more power if the rest of the fuel system is in good condition.


Mercedes does recommend periodically checking it with a gauge but again is seldom done. This very old fuel design system is both really durable and reliable if a general maintenance check is done every few years. Otherwise the chances of being stranded along the road somewhere are increased. Most maintance is also cheap to do.

"WHY"
 

In addition to the other replies ;

Because I personally have opened quite a few of these and _every_single_one_ has had a worn out spring ~ not only do coil springs have a finite life span but the check ball sits directly in the end of the spring and moves constantly, this wears the open end of the spring until it fails ~ many I have seen were paper thin and crumbled when I touched them .

As mentioned, older German cars/mechanics/engineers all assumed you'd be endlessly under the hood cleaning, adjusting and testing things .

A Mechanic I know was trained in Germany, by Mercedes but thinks they're '****' because of this aspect ~ he drives a Lexus and will trade it in long before it reaches 80,000 miles so he sees no point in doing the things we Diesel Heads consider normal .

As an update: I am currently all sold out and none have been ordered. To the various folks who have PM'd me or emailed me, I will post here when I get some. Generally, I do not reserve parts, nozzles, et cet., and that would include OFV springs. Unfortunately I take this stance because too many forum members have screwed me around in the past by emailing me or PM-ing with this or that request for nozzles, parts, et cet. I would go get nozzles, parts, et cet., and then I would never ever hear back from the forum member, not even "I sold that car" ... "that car got in a wreck" ... so I got stuck holding stock until I could sell it.

I am anticipating getting maybe an order of around 50 so that would be plenty for folks who want one.

Thanks in advance.

Cash in hand... Just saying. :-)

Cash in hand and ready to purchase as well.

Please keep us posted..

Thanks.

I also would like to purchase one of these upgraded overflow valves when they become available again. Please keep me up to date. Thank you.

Count me in for purchase of upgraded overflow valve. I can return you an empty housing if needed (you know the story).

In stock very soon !

Thanks everyone for your patience.

https://dieselfuelinjector.guru/shop?olsPage=products

When you see no change after the spring change. If there also is no overflow from the relief valve. Or none existing before the spring change even.

It is probable there is not enough fuel pressure being applied to the base of the injection pump to start with. Possibilities are tired lift pump, Dirty tank filter or even the fuel filters up front.

Constant overflow to me is an indication that the pressure regulation change or the original configuration is regulating the pressure. Plus the applied pressure does exceed what is needed for the relief valve to function properly.

If you use a fluid dampened gauge. Put a close off valve in the line to it. Those strong pulses the injection pump elements generate can and probably will destroy any typical gauge. So you want to sample the pressure. Not monitor it over a period of time constantly. The harbor freight 0-60 pound cheap liquid filled gauge is more than adequate. It was around ten dollars for a very long time and may still be in America.

One thing not discussed at all so far is a pressure reading at speed. Under loaded conditions. To me this is also important. So I guess the best ideal is a long hose to get the gauge back into viewing range at speed.

Too many people think they do not have enough boost. Or just do not think it is safe to pass. When the reality is the engine is fuel starved for all practical purposes. Really degrading the potential performance.

My suspicion is when the operational pressure drops too low at speed. The engine is out of good power balance as well. Simply because a decent pressure makes the engine a little quieter at speed. This has been reported far too many times to ignore.

I also feel like a broken record. Until I can or someone else can come up with an alternative reasonable answer. Low fuel supply pressure on the 616 may be the cause of the number one rod bearing failure.

In fact if I did buy another 616 engine and it had very low fuel pressure. The engine is noisy enough to cover a wearing rod bearing. I would plasti gauge that bearing. Easy enough to change bearing shells on the first cylinder rod. Before the crankshaft gets scored up.

I suspected that damage may be created over a very long time of running low fuel pressure. Readers probably are aware that the first rod bearing is usually the one to fail. Especially on the 616 engines. Less so on the 617 engines. Yet still happens more than not. To me it trumps having to change an engine out down the road.

Also the 616 lift pump can be upgraded to a higher output pressure just by changing the lift pumps regulation spring from a 617 turbo engine. Leaving the lift pump as original makes the fuel filters restricting effect greater as it ages. Plus it will help to keep that higher pressure relief valve functioning better.

In manufacturing the 616 engines lift pump. It was designed to have a lower original output pressure. Same as the naturally aspired 5 cylinder I think.

Before I entered the picture it was assumed the first rod bearing failed because it was the last bearing on the crankshaft to see oil pressure.

At the time I was asked why they failed. After a lot of thought. I felt the old answer just did not hold water. Both engines have about the same oil pressure. The number one bearing on the 5 cylinder is even farther away.

Plus the loading of the cylinder is greater on the turbo five cylinders. So technically in my mind it should fail more than the four cylinder 616 engines experience.

Make no misteak though at the same time if a rod bearing fails even on the 617. Chances are very high it will still be the number one or two rod bearing on them.

When most of us acquired these cars they were old already. So I also considered the possibility of sludge build up in the oil passages from the lack of oil changes. Then again if this were the case. The oil has to travel farther to get to the number one rod bearing on the 5 cylinder. Leaving me with the only other difference being there are more power strokes per revolution on the 5 cylinder than the 4 cylinder . At the same time the five cylinder turbo power strokes are much stronger.

To remove sludge an old engine. I thought that a quart of miracle mystery oil in the base. Say every second oil change for awhile. Would slowly reduce it. It seems a bad ideal to get it all loose faster. That can block oil passages you are trying to clean. With resulting destructive results. Although people switching over to synthetic oils have not reported the problem either. It does have a cleaning action as well.

There also where some other considerations. Operational RPMs are higher on the 616 on the highway for example. So my only certain conclusion was it is better to have good operational fuel pressure than not. With one perhaps still remote possibility. That otherwise it might also shorten the engines life substantially by not having it.

I designed a test to perhaps prove the concept. It is an involved test and could cause me pain in also indicating something else to investigate. So I just made sure I had good operational fuel pressure on my cars.

So I leave this post with if a spring is changed and there is no difference. Either you had high operational pressure before. Far more likely though is you have another problem present in the same system as well.

This area in general is about the cheapest area to restore. Yet there has been massive resistance to even checking it out properly. In the majority of cases it is also great preventative maintenance to reduce episodes of quitting on the road.

Things that are becoming sub standard in the fuel supply system generate gradually lower and lower than desired fuel pressure readings first. Usually the fuel supply system just does not suddenly pack it in from being a good normal one on these cars

Plus as a fuel filter builds resistance to flow. The pressure differential across it increases because of the lack of changing it. This could force more dirt through it than intended by the filter designers. I could write a manual perhaps on what preventative maintenance should be done. To stop all too many cases of premature engine failures.

I am very lucky in that all four of my 616 and 617 engines are in very good condition overall. One original engine in a car with a perhaps honest 165 thousand miles and another being a total drop in by a Mercedes dealer not long before I aquired it. Years ago now. Both those cars indicate to me just what they were like when pretty new performance wise.

SPRINGS JUST ARRIVED TODAY. I will get all back orders out in the mail tomorrow. Thanks everyone for your extensive patience

Perhaps this is a stupid question, but searching here and via google to see other forums....

What is the process to remove the lift pump for refurbishment?

Ive pulled the spring before with everything on the car. Measured fine. But it seems like this would be a smart mod to do in general, and if doing this, might as well update these nearly 40year old pumps at the same time.

I can't seem to find a good pictorial or write up. I'm just not sure if it's particularly complex or if there are any issues to watch out for.

I did find a good OM606 how to on here but that's not a 616/617.

Thanks!

It's pretty easy. Three nuts and a paper gasket keep the pump flush with the Injector pump. First remove the fuel filter line. Next remove the primer pump, you should then be able to remove the plastic line compression fitting to the secondary filter with a flare nut wrench. Loosen those three nuts and back the pump off the studs.

Once you remove the pump, you want to remove the flare fit/mount, the spring and valve is underneath. On the bottom of the lift pump under the port you connect to the primary fuel filter, is another nut that gives you access to another spring and valve. On the back of the pump, there's a roller/cam lobe/tappet (forgive me) that interfaces with the IP that you can disassemble and remove. Once you remove the plunger, deep in the bore is a tiny o-ring you can replace (keeps oil and fuel from mixing). The giant hex head in the front of the pump contains the main pressure spring. Apparently, if your spring is not broken (99% likely to be fine) it's a good idea not to mess with removing that cap to replace the crush washer -unless of course it's leaking which is equally unlikely. Getting all this stuff off the pump when it's not mounted is a b_stard. Lots of soft wood in a vice so you can crank down on the nuts with a breaker bar and deep sockets. Just be careful when you're mounting the pump in the vice that you don't clamp down on that flange (the one that mounts to the IP) as apparently it's a little fragile.

It's an easy job, just a little annoying because some of those valves/nuts/attachments are on pretty tight. I had a nearly impossible time removing one of them -nothing fit but a crescent wrench which stripped painfully with every turn. Later had help with an angle grinder removing a small bit of metal to fit a socket, then no problem.
When you reinstall the pump, use Gasgacinch or permatex high tack sealant on the studs and the gasket -mine leaked with the new gasket alone.

Thank you very much, this is a wonderful write-up!

http://www.peachparts.com/shopforum/attachments/diesel-performance-tuning/125547d1415060926-performance-overflow-valve-valve-2.jpg

Can someone measure the ball bearing and give me a dimensions?




I must have lost it and am wondering if I use a ball bearing from something else that is 5.9 mm/.23 inches

Its either 6.00 or 6.35mm and probably along the lines of G10 or better.

It's 6.00 mm

Out of my current batch, I have aroud 50 left for the PMs I got. You can order here or at www.dieselfuelinjector.guru

Different check valve I pulled from a junkyard... not able to be changed to a better spring. Glad I didn't have this one...
Well I'm going to stay with my 5.9 mm instead of cutting my junkyard unit to get the ball bearing.

Plenty of springs left for 2019 ... around 60+

www.dieselfuelinjector.guru

Greazzer.... any updates to the overflow valve for the turbo OM606? If you recall, they were of different designs than NA OM606 and prior diesels.

Trying to get bodies made for the OM606 so I could sell the whole unit for $40 shipped. Not an easy task. No one in the USA wants to get involved and the folks over in China and India are not working out as hoped. I got a bunch of time invested and still working on it.

Might be easier to get an adaptor.

Amazing information. Had to quote it,

I'm about to go through the entire fuel system with a diesel purge, lift pump rebuild, overflow spring replacement, modified tank outlet with electric fuel pump added, and fuel strainer by pass to see if it's the cause of my low power.

Why pull fuel when you can push with an electric pump at the tank.

I'm going to put mine right by thr tank

UPDATES:

36 springs left and that's it. I have 8 whole units.
Springs are still $35. Whole OVF $45 with $5 core back

OM606 FULL OFV - Coming up in a few weeks. Will float 10 of these out there to see how it goes. $45.00 shipped CONUS Priority Mail $50 insurance and tracking

I'll take one for om606.

Can a 606 ofv be back for to a 603?

617 ones work on 603. It's a tight squeeze during installation against the temperature sensor on the block, but fits fine.

Does the 603 have a hand primer?

No.

hi ,how much to inclued shipping to ireland , please reply ,ive a 1985 616 n/a in a 207D camper .

danny

No clue. I would say not more than $42 extra. I suggest paying $50 for shipping, and I would refund the difference relative to shipping. Shipping in CONUS is $8 USD. So, $42 extra. For example, if shipping was $48, you already have $8 "built-in", so that would leave $40. I would refund you $10 from the shipping out of the $50. Hope that makes sense.

I just bought your last OFV! :D

This is for a NA616.
I assume will be fine?

Yup. Last one in stock. Thank you for the order. It will ship tomorrow

I bought the OM603 OFV on greazzer's site and received the OFV as shown in the picture:

https://isteam.wsimg.com/ip/c41dcb4f...rs=w:960,h:720

however after pulling the OFV on my 1987 300TD it appears the stock OFV on my car is quite a bit shorter:

https://dm2pap090files.storage.live....&cropmode=none

Of course I still tried to install it even though I was pretty sure it wouldn't fit. You can see here there the new OFV bottoms out with a pretty big gap:

https://dm2pap090files.storage.live....&cropmode=none

Assuming I'm installing it in the correct place on the pump is there any reason my pump would have smaller/shorter OFV than others?

I've previously purchased an OFV and injectors from Greazzer for my OM617 with great results, so I'm assuming my I'm either doing something wrong or have a different pump than other OM603 engines. Hoping someone might have some insight here.

thanks

I posted about this in his for sale thread in the parts subforum of this site. The 603's use the same size overflow valve as the 61x engines. The long bolt is for the 606 engines. I assume he has not updated his website to reflect that.

If you purchased the wrong one please mail it back to me and I’ll refund your money

Thanks Greazzer :)

Following up with you in email.

Hey, I emailed you, and refunded you the difference. I have one is stock waiting for you. Please PM or email me your address and please ship the other one back if you do not want it.

Down to the last 14 springs.

Got the OFV spring installed and the rebiult injectors installed. All I can say is wow what a difference. My plan was to install the injectors first and the OFV later so I could evaluate the changes with each component but I got to excited and installed it all. I never realized how smooth these engines are supposed to be. A huge thanks to Greazzer for the amazing work he does.

Many thanks for the kind words.