'88 750iL cooling system problem

[retnavy]

Just changed waterpump and there is no coolant flow. Got car couple months ago, no thermostat. Bled air as best I could. Radiator seems clear, poured water in top hose and wathced it run out return hose and bottom drain. Added coolant into recovery tank until it came out bypass hose port on radiator and out bypass hose. What am I missing? Any help would be appreciated! Thanks in advance!

[Bear]

Sounds like you did everything correct, on many of the '88 the coolant bleed was an automatic thing (my 11/87 build date was one of them). here is a website you might find helpful http://bmwe32.masscom.net.

[retnavy]

Thanks, I've already been to that site too... Can anybody help???

[Bear]

Tell us more, is she overheating, yes/no. If no circulation and water pump is good, could water jackets be blocked. have you replaced the thermostat and tried to run her . Some of these cars are very difficult to bleed the air from the system, go to Dan Gales website:
http://www.nmia.com/~dgnrg/page_2.htm
This is predomanitely a M30 site, but the bleed procedures are much the same.

[retnavy]

Been thru the bleed proceedure, still no flow. Yes, it will begins to overheat if I don't shut her off, no coolant flow. Radiator hose to inlet of radiator does not get hot. At present, there is no thermostat, yet. Got the car couple months ago. I suppose it's possible the engine block is plugged, ugh!!! I did find the hose that looks like it goes to one side of the heater core, one side of the "y" tube from the recovery tank, connected to another hose that attaches to the driver side coolant header??? Not sure what to do from here? Probably pull the engine block plugs and see if she drains out???

[Bear]

Do you have a Bentley manual, if no go to http://www.realoem.com for a look see at the hoses, also I would post your problem at roadfly.com, a lot of technicians at that site and they may also be able to help.

[Bear]

If you go to Don Gales website, look at the misc jpegs, especially the hand drawn ones of the heater hoses and the ones from the expansion tank to the thermostat. Yo u may want to blow the lines out from the expansion tank forward.

[Bear]

Another thought, do you have the correct expansion tank (coolant recovery tank, the one at the firewall) cover. The new cap (via recall) is flat on top, the old cap had a small, raised circle on top. Old cap, no pressure release, overheats.

[retnavy]

The coolant recovery tank is on the firewall and has the cap that is flat, no ring, just the lettering for the warning about removing cap when hot. Question, do these engines require the thermostat in place for the coolant to flow? Like I mentioned before, I got the car a couple months ago and found out there is no thermostat installed???

[retnavy]

Also, I just pulled the pump again due to one of the orings didn't seal and leaked, I removed the recovery tank and poured water into the hose connected to the header on the driver side. Poured out as fast as I poured it in. Cracked open the block drain on the driver side and coolant came out of that. Couldn't get passenger side block drain off.

[Bear]

Well it sounds as if the pump is good, did you take a look at Don Gales site under coolant bleeding and look at the small hole where a dribble of coolant should be moving. At this point, I would go to www.roadfly.com and post what you have done and what is happening, there are a lot of BMW techies over there and they have rescued me and my '88 750 many times.