gjm 3193 Report post Posted November 10, 2015 I've been told that an E21 I've been looking at has the wrong fuel pump fitted, and that it doesn't supply enough pressure. This is a 320/6 - carb model... Surely that doesn't require much pressure? So... Does anyone have a spare pump, bearing in ind these appear to be specific to the E21 and E12? Or would I do better (as I suspect) to get a low(ish) pressure electric pump? I expect that'll potentially lead to requirements for a pressure regulator... 1 Quote Share this post Link to post Share on other sites
hotwire 352 Report post Posted November 10, 2015 Is it not the original pump in it Graham? It would seem unlikely to have an incorrect pump fitted as it would be specific to fit the M20 My E12 still has the pump on it although it has not been connected or pumping fuel for years - since i converted it to Ljet. That said - the diaphram is probably buggered by now. I had meant to remove it & fit the blanking plate from a motronic engine, have just never got around to it. Quote Share this post Link to post Share on other sites
gjm 3193 Report post Posted November 10, 2015 Is it not the original pump in it Graham? It would seem unlikely to have an incorrect pump fitted as it would be specific to fit the M20 My E12 still has the pump on it although it has not been connected or pumping fuel for years - since i converted it to Ljet. That said - the diaphram is probably buggered by now. I had meant to remove it & fit the blanking plate from a motronic engine, have just never got around to it. The PO tells me he has replaced the fuel pump (not said why). It's not clear if he's talking about the engine-attached unit (p/n 13311272406) or the sender unit in the tank (p/n 16121114254) - I'm verifying details. While these are a bit scarce (I expect) the good news is they appear to be rebuildable: RealOEM shows parts for this. Quote Share this post Link to post Share on other sites
scottbeattie 63 Report post Posted November 10, 2015 I've been told that an E21 I've been looking at...On a side note, where does one find an E21 these days? I've wanted one for ages, love the shark nose era Bimmers. I "settled" for the E28, the inverted commas are there because I wanted an E28 as well!Sent from my iPhone using Tapatalk Quote Share this post Link to post Share on other sites
gjm 3193 Report post Posted November 10, 2015 On a side note, where does one find an E21 these days? I've wanted one for ages, love the shark nose era Bimmers. I "settled" for the E28, the inverted commas are there because I wanted an E28 as well! One occasionally comes up on TradeMe or on here, and they may be a little more common than a 2002 but it's a close thing. I found this one by word of mouth, but haven't yet seen it. Quote Share this post Link to post Share on other sites
scottbeattie 63 Report post Posted November 10, 2015 Ah I see. There were 2 or 3 on TardMe just before I got the E28, they all obviously sold before I got to 'em though. Sent from my iPhone using Tapatalk Quote Share this post Link to post Share on other sites
aja540i 1896 Report post Posted November 10, 2015 I converted one of mine to an electric diaphragm pump, if you buy the right pump you shouldnt need a pressure reg, they come in a couple of different pressure ratings. Just be careful mounting the pump, they can be a bit rowdy and really need good rubber isolation mounts. You will also need to run a relay and some wiring but im sure youre up to it! Not sure if it helps but i have a couple of old M10 fuel pumps that are just taking up space in my garage? Quote Share this post Link to post Share on other sites
gjm 3193 Report post Posted November 10, 2015 I'll check to see if the M10 pump is compatible. I'd probably have preferred an M10 engine, but I'll settle for a solid car! Could you find out what pressure rating you used? Either psi or l/min? Ta. Quote Share this post Link to post Share on other sites
gjm 3193 Report post Posted November 10, 2015 The in-tank pump has been replaced with an external pump, and the original one is available. Need to find out the flow rate of the in-tank pump so any replacement (an E30 pump can be used, with slight modification) internal or external is the right size. Quote Share this post Link to post Share on other sites
aja540i 1896 Report post Posted November 11, 2015 I'll check to see if the M10 pump is compatible. I'd probably have preferred an M10 engine, but I'll settle for a solid car! Could you find out what pressure rating you used? Either psi or l/min? Ta. Have a feeling it was a 4-6 psi pump, which was fine for an M10b16. If you really want an M10 i have a spare 2 litre i could be convinced to part with. 1 Quote Share this post Link to post Share on other sites
hotwire 352 Report post Posted November 11, 2015 The in-tank pump has been replaced with an external pump, and the original one is available. Need to find out the flow rate of the in-tank pump so any replacement (an E30 pump can be used, with slight modification) internal or external is the right size. Graham - which car are you talking with the internal pump? E21 M20 carb, as the E12, have a mechanical engine mounted pump & will run at about 4-6 psi The E30 is Ljet & will be running an external high pressure electric at about 38 psi The later Motronic ran either low pressure in tank lift pump & external high or just internal high pressure Quote Share this post Link to post Share on other sites
gjm 3193 Report post Posted November 11, 2015 (edited) Have a feeling it was a 4-6 psi pump, which was fine for an M10b16. If you really want an M10 i have a spare 2 litre i could be convinced to part with. Personally, I think a 2-litre M10 is the perfect engine for an E21. The 6 is great, no doubt, but not so easy to work on. A shame in some ways cos I know where there is a manual 'box for a E21 M20... Still, this is intended to be Mrs M's car, and she'll need an auto. Graham - which car are you talking with the internal pump? E21 M20 carb, as the E12, have a mechanical engine mounted pump & will run at about 4-6 psi The E30 is Ljet & will be running an external high pressure electric at about 38 psi The later Motronic ran either low pressure in tank lift pump & external high or just internal high pressure Thanks Grant. This is for the E21 320/6, carb model. I know about the engine mounted pump, but there is also the sender in the tank which is the bit that appears to have been replaced with an electric pump. That said, I am most definitely not an expert on these cars and that could well be a red herring. Perhaps it's just a leaky diaphragm on the engine pump that is the issue? That could manifest as low fuel pressure. Edited November 11, 2015 by gjm Quote Share this post Link to post Share on other sites
hotwire 352 Report post Posted November 16, 2015 Yep quite likely just a tired engine pump. I guess it could have had a retrofitted in tank low pressure pump installed but it would seem unlikely Quote Share this post Link to post Share on other sites
Mr Vapour 76 Report post Posted November 20, 2015 I have alittle fasit pump running on my 320/6. I need to rubber mount it as it's a bit noisy but it works. Run it off a relay that's switched off the ignition. did I see you say that you had not seen the car yet?? Quote Share this post Link to post Share on other sites
Mr Vapour 76 Report post Posted November 20, 2015 But it's only noisey when the motor is not running. Once it's running you can't hear it . Quote Share this post Link to post Share on other sites
gjm 3193 Report post Posted November 20, 2015 I have alittle fasit pump running on my 320/6. I need to rubber mount it as it's a bit noisy but it works. Run it off a relay that's switched off the ignition. did I see you say that you had not seen the car yet?? That sounds good. And no... Not seen the car yet! It's quite a trip on the off-chance that it may or may not be OK, so I'm paying for a WoF (which I expect it to fail). Quote Share this post Link to post Share on other sites
