m51 diesel

Hi -
sorry my first real post is a dumb question. but if you can't help, at least you might get a laugh.

I have a 1992 classic, but its got a 1998 325td m51 engine.

so - my FIP was leaking a little, so I thought I'd take a look - I took the inlet manifold off. In the process of taking it off, I disconnected a couple of electrical connectors - I remember three, one to the air temperature sensor in the manifold per this diagram:

RealOEM.com * BMW E36 325td INTAKE MANIFOLD SYSTEM-AGR

and one to the remote temp sensor per this diagram.

RealOEM.com * BMW E36 325td Cylinder Head Attached Parts

and probably a 3rd - which I don't know what it is, but its attached to a thing with two vacuum tubes - one to EGR valve I think (on front of inlet manifold) and other going off under the manifold. This electrical socket is mounted on the mounting bracket numbered 8 in the first diagram:

RealOEM.com * BMW E36 325td INTAKE MANIFOLD SYSTEM-AGR

Having removed the manifold, I took the top half of the FIP off, put some sealant on it and reassembled it.

So far so good. I put the manifold back on, and was confident at the time I'd reconnected the leads correctly. But...
It didn't start. so perhaps I need to prime the FIP up somehow, but I'm also not so sure I've connected the leads correctly.

I've got two leads coming from the ECU (it looks like) - one plug with black colouring inside, one with blue. Both of them can reach all 3 sockets.
I've got another lead with blue inside the plug coming from the little black box that powers the glowplugs. this one can only reach the brown remote thermo on the head and the air temp sensor in the manifold.

Please can anyone offer any advice on which goes where?


:doh:

the M51 Engine is the same engine thats in the P38 check out the FIP wiring on that & you should be sorted

In Fact get a copy of RAVE (it has the P38 Diesel)& use it as a reference manual for your Engine.

Do I understand correctly, that you part dismantled the FIP in situ?

Most garages & workshops won`t go into a FIP. They are most often sent off for checking/refurb. Stripping `em down is highly specialized & should only be done in clean conditions. Small bits of contaminant can make for big problems. Hope I misunderstand your original post...

thanks - no, you didn't misunderstand.

I'd read a few threads elsewhere where folk have described how specialised it is, and conversely that it's straightforward. ish. -so I took a chance - and having done it, it seemed easy enough to keep it clean and not complicated - just two parts separated and went back together again. Not my usual experience of taking things apart and springs and widgets flying out everywhere.

jonbill said:

thanks - no, you didn't misunderstand.

I'd read a few threads elsewhere where folk have described how specialised it is, and conversely that it's straightforward. ish. -so I took a chance - and having done it, it seemed easy enough to keep it clean and not complicated - just two parts separated and went back together again. Not my usual experience of taking things apart and springs and widgets flying out everywhere.

Click to expand...

might of overcooked it could be foooooooooooooooooooooooooooookered

gtland said:

Most garages & workshops won`t go into a FIP. They are most often sent off for checking/refurb. Stripping `em down is highly specialized & should only be done in clean conditions. Small bits of contaminant can make for big problems. Hope I misunderstand your original post...

Click to expand...

Naah, any idiot can strip um down, it's rebuilding them correctly that's the hard part.

when you strip the top bit of the pump you should have just replaced the seal its only about £2.50 and if you remove the bit below it you have to set it up or it wont start,this is held on with the remaining 3 bolts,but the actual bit is elongated for adjustment and controls throttle response etc,you just slightly slacken and adjust when the engine is running till you get it tiking over about 750 rpm,maybye you have disturbed this and thats how it wont start

Thanks everyone - I've got RAVE now, although as you've all pointed out, what I did to the pump is probably the suspect bit. (I've tried the electrical connectors in all 4 combinations).

I can see by some shiny marks by the bolts that I haven't put the middle section back on where it previously was - so I guess I've got a hope of realigning it to those marks. That'll have to wait to next week-end now.
b*ugger, its a miserable bike ride to the train station in this weather

@ wullie: Quick follow up question - does the positioning of the FIP body change the injection timing or quantity of diesel injected?

jonbill said:

@ wullie: Quick follow up question - does the positioning of the FIP body change the injection timing or quantity of diesel injected?

Click to expand...

It changes the timing.

Thanks Wammers - that explains why it makes the difference between working & not working. (as opposed to running rough, which enriching/weakening would do I think)

rather a steep learning curve this diesel malarkey.

no it dosent affect the timing,thats set by a dti from the end of the pump,but even if the timing is out these pumps have electronic compensator so it automaticly adjusts the timing,but the middle section you talk about if you have had it lifted you need to make sure the small dowel like pin locates in the hole on the only way i can describe it is round bit that slides on the shaft,when setting it up try and put it where it was tighten the bolts tight enough so you can move to adjust, this is micro adjustment and controlls throttle response, tickover/idle hope this helps

wullie said:

no it dosent affect the timing,thats set by a dti from the end of the pump,but even if the timing is out these pumps have electronic compensator so it automaticly adjusts the timing,but the middle section you talk about if you have had it lifted you need to make sure the small dowel like pin locates in the hole on the only way i can describe it is round bit that slides on the shaft,when setting it up try and put it where it was tighten the bolts tight enough so you can move to adjust, this is micro adjustment and controlls throttle response, tickover/idle hope this helps

Click to expand...

Are you absolutely sure? How do you set the timing with the DTI then. It is set to thous with the DTI, two setting depending on chain stretch. Moving the pump does not effect the timing. One word bull****.

the timing is set to 2 degrees by loosening the end bung on the pump screwing the dti in setting up,loosen the two bolts that hold on the pump and turn clockwise or whichever to the timing,when you lift the first lid from the pump you see the throttle potentionemeter this is what you adjust when you move it forwards/backwards

wullie said:

the timing is set to 2 degrees by loosening the end bung on the pump screwing the dti in setting up,loosen the two bolts that hold on the pump and turn clockwise or whichever to the timing,when you lift the first lid from the pump you see the throttle potentionemeter this is what you adjust when you move it forwards/backwards

Click to expand...

The pump timing has to be set very precisly static. 0.004" +- 0.001" reading on DTI for engines with less than 20,000 Km and 0.0035" +- 0.001" reading on DTI for engines with more than 20,000 Km. This to allow for chain stretch. Last movement must be towards engine. The available advance/retard provided within the pump is there for varying engine speeds and temps either side of static and is not enough to make up for the pump being thrown on from across the workshop. So moving the pump body does affect the timing.

Thanks Wullie - is the dowel pin you mention just a few mm tall? (3 or 4?) - sat on top of a plastic mound a cm or so high?

someone mentioned buying seals for this for £2.50 - does anyone have a reference for where to buy online? Mr Ebay's emporium doesn't stock one.

yes thats the dowel pin,its easy to assemble and think you have it in the hole you build it up and you havent, no matter what you do it wont start, ive done this many times use a good torch and a mirror and be patient, as for the seals you need to contact a bosch agent with your pump no or hope a diesel injection specialist can supply you them

Thanks Wullie. that gives me hope. I certainly did nothing to attempt to locate it - didn't know it located anywhere. I thought it was just going to swim in a puddle of diesel.

Fastline in Northampton near me sound like they have the seal parts.

my fingers are crossed!

let me know how you get on, if you need any more help i will do what i can