New E9 owner in Seattle...what did I get myself into?

[Bionicgold]

Greetings E9 enthusiasts and fellow owners. I recently purchased a '73 3.0 CS in what I believe is Baikal Blue with red leather interior. I'm very new to the world of classic BMWs and the E9 in particular so I'm grateful for this forum and all the collective wisdom and experience of everyone here. I'd love to meet up with some of the local Seattle guys here to learn some of the basics of E9 ownership.

One thing already that I'd love to get some advice on. I got a pre-purchase inspection done a month ago before buying the car and everything checked out great. No rust issues, mechanically sound with the minor note of a leaking water pump and power steering pump. I had it shipped to Seattle and have only had time to take it on very short trips locally (less than 3 miles). Here's the issue. Last time I drove it, the temperature spiked just a few blocks after leaving the house so I turned around and came home. The temperature quickly dropped back down to normal. The quick temperature swings seemed odd, so I thought perhaps it was a bad sensor or maybe an air pocket in the cooling system (perhaps due to the water pump leak? photo attached). The next day, I topped off the coolant and started it up and let it idle to see if the temperature would jump again. No overheating, but there was white smoke at startup (steam?), which I've noticed before to varying degree, but it seemed more than usual. After a while, the white smoke clears, but I'm worried that it's caused by coolant getting into the cylinder heads somehow. Again, it passed the PPI with flying colors and there were no indications of any issue the first couple times I drove it. I haven't noticed any oil in the coolant or vice versa. I was going to take it to a local shop to have the water pump/power steering pump leak addressed, but now I'm worried about driving it at all. Any thoughts? Any local Seattle guys around to chat? Thanks!

 

[HB Chris]

If temp stays normal while idling but goes up when driving you most likely have a partially clogged/blocked radiator.

 

[Bionicgold]

Thanks, HB Chris! I appreciate the feedback.

 

[Stevehose]

If you've just aquired the car with unknown service history (even if known) I'd replace the water pump, fan clutch, and get the radiator serviced. Also alternator and all ignition components (plugs, wires, rotor/cap, condensor, points etc.). That way you have peace of mind and your chances of being stranded somewhere have dropped dramatically. Beautiful car.

 

[Markos]

Welcome! Seattle has quite a few e9 owners. Some of them are serious e9 experts be in mechanical, body, or history. Only about half of the 20 or so active owners can be found online. Most have accounts but post infrequently.

I've learned quite a bit about parts and how these cars go together due to tinkering and sourcing parts for my project car. My seat time can still be measured in minutes. I only drive my car for about 15 minutes every two months. Looks like you have a complete car so you are in good shape there!

It's unlikely, but check the casting on the head near the intake manifold. It helps if you remove the filter box, which is very easy to do. The early heads frequently crack. Just about every car has a later model head. Given the white smoke on startup it's worth a look.

Both of my heads have been replaced so I'm not actually sure where the markings are on the early head. @HB Chris should know.

I'm always happy to chat about this stuff. I spend two hours in the car daily so feel free to give me a ring. Shoot me a PM if interested.

Check with @bimbill on his east side mechanic. He isn't on here all that much but a PM should go to his email. Bill also heards some of the Seattle e9 cats...

 

[Bionicgold]

Stevehose/Markos, thanks for the info! I'll see what I can find out about the casting on the head. From what I understand, it's a very original car (still has Zenith carbs and original smog equipment) so I wouldn't be surprised if it still has original heads. I appreciate the invitation to chat further. As I mentioned, this is all new to me and I have a lot to learn.

 

[Stevehose]

the head has a casting date on the front part of the head driver side between #1 and #2 cylinder intake. If original it will have a number 73 surrounded by dots which indicate the month. My '72:

 

[Bionicgold]

Thanks for the image. Looks like I have a '75 head, so it's been replaced in the past. While I was looking, I took the cap off to look inside and there's a milky residue on the underside of the cap. That's conclusive evidence that coolant is getting inside, right? Sooo, worst case scenario? cracked head or blown head gasket?

 

[Stevehose]

worst case cracked head, best case blown head gasket. Pre 84?? heads are prone to warping and cracking.

 

[Markos]

Thanks for the image. Looks like I have a '75 head, so it's been replaced in the past. While I was looking, I took the cap off to look inside and there's a milky residue on the underside of the cap. That's conclusive evidence that coolant is getting inside, right? Sooo, worst case scenario? cracked head or blown head gasket?

Obviously check with a mechanic but coolant will make your oil milky. As mentioned, the white smoke is another indicator. Oil burns blue and has a distinct smell.

I believe the new casting didn't start until '82 Regardless of whether it is the head gasket or a cracked head, you are going to want to swap the head. Since you don't have the original head anyway, it makes no sense to keep crack-prone head on the car.

The good news is that heads are easy to find. You should have no issues finding one in Seattle. I'd give you mine for free but somebody tapped the mechanical fuel pump hole to plug it. Be sure to swap your cam because the e9 has a 272 cam unlike the later models.

More head info here:
http://www.firstfives.org/faq/cylinder_head/cylinder_head_faq.htm

 

[bimbill]

Before you assume anything, there are several tests that can be done to narrow down the cause of your symptoms. If combustion gases are entering the cooling system, which would result from a head gasket failure or crack between the 150 psi plus pressures in the combustion chamber and the 15 psi of the cooling system, it is unlikely that white smoke/steam coming out of your tail pipe would go away as the engines warms. At least from my experience it would get worse. There is a chemical test that can detect hydro carbons in the coolant but the car has to left overnight to perform that one.

At the least, if it was my car I would have water pump replaced and the cooling system flushed and filled with BMW factory coolant. If you wanted to go a step further you could pull the radiator and have it checked and cleaned. I can recommend a very good, old school radiator shop in the local area. A completely refreshed cooling system would be money well spent regardless of whether that fixes your problem.

 

[Markos]

Thanks for chiming in Bill. Good approach on the test and tackling the low hanging fruit first.

I had the chemical test done on my Jeep last year. I was absolutely convinced that my head gasket was *not blown, and my head was not cracked. They did the test which found traces of combustibles in the coolant. Still not convinced, I replaced the radiator. Like the OP I was showing signs of a clogged radiator. You could actually see the lower radiator hose collapse at WOT. Anyway I finally gave in and accepted the conclusion. The Jeep is in IL so I can swap the head gasket until next summer.