89 325i Over heating - BMW Forum

rob714 · 03-29-2009, 07:58 PM

So, I just picked me up a nice 89 BMW 325i. It has a few problems that I am working out. The biggest thing I am struggling with is I am having a problem with it overheating. I flushed the radiator, changed the hoses and and refilled it. The fan works and the fluid seems to flowing freely. I haven't seen any leaks anywhere either. Any suggestions on what to check? I am running out of ideas! Thank you for any help!

witeshark · 03-29-2009, 07:59 PM

Are you sure the water pump is good?

rob714 · 03-29-2009, 08:02 PM

Hmm... no, Im not positive, do you know a way to check and see if that works?

rob714 · 03-29-2009, 08:17 PM

When I started it the other day and I had a bad hose it sucked flat so it was definitely building up pressure.

witeshark · 03-29-2009, 08:20 PM

Do you know if the pump was changed with the last timing belt replacement? How old is the radiator? Maybe is has blockages.

Edit: moved to the E30 section for better notice.

johnnyBgood · 03-29-2009, 08:42 PM

Quote:

Originally Posted by rob714

Hmm... no, Im not positive, do you know a way to check and see if that works?

Normally with a functional pump you have a good flow through the radiator @ operating temp. With a defective pump, you could have little to no flow, it also could be noisy, & show signs of leaking. With that said, the 1st & easiest thing to do would be to check & replace the thermostat......run the engine to normal operating temp. & then feel the upper & lower hoses. They should feel about the same in temp., if one is much hotter than the other, then the t-stat is stuck closed....& needs replacing.

Note: if you are not sure when the water pump was last replaced & you are going to replace the t-stat, it just makes sense to replace both the t-stat & water pump....together due to the fact you might not know when the water pump was last replaced.....

rob714 · 03-29-2009, 10:26 PM

Okay, so the pump is working, no leaking and its not making any noises. I am gonna check the t-stat tonight. I am pretty sure the radiator is good too. The thing is it sat for about 6 months before I got it, it smokes a little and starts hard sometimes too. I figure all that is sediment and water in the fuel. I am running some lucas cleaner through it to see if that helps. Hopefully that helps a get it running smoother.

silversled · 03-30-2009, 07:25 PM

why wouldn't you do the thermostat with the water pump anyway. Your right there anyway.....as long as you are there you might as well do the timing belt and tensioner....heck...it's all labor....

rob714 · 03-30-2009, 07:44 PM

Quote:

Originally Posted by silversled

why wouldn't you do the thermostat with the water pump anyway. Your right there anyway.....as long as you are there you might as well do the timing belt and tensioner....heck...it's all labor....

Yeah, I would except this guy is broke! I spent all my money on the car! But I did change the thermostat and that seemed to do it. I think it was just sticking. I flushed the radiator again and I put in a cleaner and then I will flush it again tomorrow. It is running much better now, it still starts a little hard and seems to be a little weaker than it should be. Keep in mind it sat for 6 months before I got it. You think the injectors could be bad? I am gonna change the plugs tomorrow but I can't afford anything else til friday. Thanks for all the great advice so far!

silversled · 03-30-2009, 07:49 PM

actually, you haven't really described what's wrong with the running of the car....what's not right here?

johnnyBgood · 03-30-2009, 08:01 PM

Quote:

Originally Posted by rob714

Yeah, I would except this guy is broke! I spent all my money on the car! But I did change the thermostat and that seemed to do it. I think it was just sticking. I flushed the radiator again and I put in a cleaner and then I will flush it again tomorrow. It is running much better now, it still starts a little hard and seems to be a little weaker than it should be. Keep in mind it sat for 6 months before I got it. You think the injectors could be bad? I am gonna change the plugs tomorrow but I can't afford anything else til friday. Thanks for all the great advice so far!

Quote:

But I did change the thermostat and that seemed to do it. I think it was just sticking.

Good for you....at least you found the problem, as far as the water pump & timing belt, you can do that another time, it would of been ideal for you to do it all at once, but at least you fixed the problem......

Quote:

Thanks for all the great advice so far!

You are welcome.......anytime!

johnny,

rob714 · 03-31-2009, 11:20 AM

Thanks! Um, well it starts a little hard and it has a rough idle some of the time. Its not major but a little bothersome cuz I don't know what it is. Then when I give it a little more gas on the highway it acts like it can't decide if it should drop gears or hold the one its in. I have checked the tranny fluid and it was good. And it doesn't slip, just seems to confuse the gears I guess.