The BMW is Alive!

[evan_flatt69]

Well if you guys didn't know already, I bought a second vehicle: a 1985 BMW 635 CSi (Don't worry I'm not selling the truck). I already love this car.. The handling is fantastic and it an overall sexy car.

Anyway, here in Middle Tennessee any vehicle newer that 1975 has to pass emissions. And of course my new car's HydroCarbon tailpipe readings came in at 386ppm where the limit is 220ppm. After a little research I've figured out that high HC readings are due to unburnt fuel. Which means it's probably just in need of a good tune up (60$ DIST cap, 20$ rotor, plugs, 50$ O2 sensor, and seafoam) and hopefully not a new catalytic converter. So looks like I'm going to be fiddling with the BMW and replacing the starter on my truck this week. I'm not looking forward to doing the starter.. It is going to be a BEAR to change. I knew it was a bad idea to let the exhaust shop weld the pipes directly onto the headers. Maybe I can find a way to do it without cutting the pipe off. At least it will tesch me to use exhaust wrap this time around.



I'll go ahead and post a pic of the car for the guys who haven't seen it..



Nearly 30 year old sport coupe for the win.. But my truck would still smoke it in a drag race.

[1972hiboy]

yup hydrocarbons are un burnt fuel molicules. Its either running rich or the cat is bad. Always a good idea to check the coolant temp sensor on fuel injected vehicles. if its bad and reading cold it will richen up the mix. You can test the cat with a infared thermo gun. it should be over 400degrees warmed up.

[rltvader]

I just replaced my starter in my truck, i used an MSD micro starter and it was SOOOO much easier to get in. My headers also get in the way, so I am going to try to draw heat away with some shorty header and connect them closer to the engine.

[67 Camper Special]

I bought one of those as a one year old.

What an awesome car! They just hang in the corners like crazy, but still ride nice and smooth. And the sound of that motor winding out is addicting. I sold it when I no longer had a licence. I consider it the last great car BMW made that a working guy could afford [barely]. Had several 2002's, still my favorite little cars.

Have fun with that thing, I'm sure you will

[evan_flatt69]

Giving the engine a good once over

[DuckRyder]

What?

[evan_flatt69]

After a compression test I found that it had about 55psi on cylinder #1. All the others were about 140psi. I ran the engine then pulled the #1 plug and it was wet so I knew It wasn't burning fuel well which was probably why it didn't pass emissions. I added oil to the cylinder and redid the compression test and it didn't seem to help any so I knew it probably wasn't rings because of that and the compression numbers on the other 5 cylinders. So I figured it was valves or the head gasket. Now that my truck can run (needed a new starter) I am going to do what I did to the engine in my truck over the summer: Probably pull the engine.. Clean EVERYTHING, paint things that need paint, replace things that need replacing, check all the electrics, new chain tensioner and guide, new gaskets, check timing chain and gears, new belts, fix leaks, re-do some exhaust, cylinder head rebuild/upgrade (maybe), new cam (maybe). I want to get new connecting rods and pistons then blueprint them but that is probably out of my price range...


Here are some pics of the cylinder head, cylinder, and #1 cylinder head gasket.. What are your guys opinions? What would you guys do?

It looks to me like the #1 cylinder exhaust valve is way darker than all the others and there is an obvious color change on one section of the valve. Is this the issue?

It does not look like the head gasket of the rings were the issue.

[Ranchero50]

Bent intake valve? Questions why #1 intake tract is so dark. Check the cam lift too.

[evan_flatt69]

Bent intake valve? Questions why #1 intake tract is so dark. Check the cam lift too.

I also noticed that but I forgot to mention it in my post.

[1972hiboy]

Couldnt #1 valve and runner be darker because oil was shot into the cylinder? Getting dry things wet often gives them a darker look.

[67 Camper Special]

My brother just totaled out a 740M, now that motor in there would be bad fast!

The exhaust valve being dark is not necessarily an indication that that valve is bad, just that the cylinder was not firing as it should. Lower temps will change the color to what you see there. You notice that the intake valve in that cylinder has more buildup on it as well.

I think the pull it and do it right plan is the way to go too. Then you know what you have. Cylinder looks good as much as I can see in a picture so hopefully its just a valve seat.

Shop around on BMW stuff, some places are crazy what they want for stuff.

http://forums.bimmerforums.com/forum/

I found this forum to be the most down to earth. Some of the BMW forums breath some pretty rare air......

Larry

[evan_flatt69]

Couldnt #1 valve and runner be darker because oil was shot into the cylinder? Getting dry things wet often gives them a darker look.

Hmm.. hadn't thought about that. But I know I ran it at least 10 minutes before I started tear down so it should have all burned up?

[evan_flatt69]

My brother just totaled out a 740M, now that motor in there would be bad fast!

The exhaust valve being dark is not necessarily an indication that that valve is bad, just that the cylinder was not firing as it should. Lower temps will change the color to what you see there. You notice that the intake valve in that cylinder has more buildup on it as well.

I think the pull it and do it right plan is the way to go too. Then you know what you have. Cylinder looks good as much as I can see in a picture so hopefully its just a valve seat.

Shop around on BMW stuff, some places are crazy what they want for stuff.

http://forums.bimmerforums.com/forum/

I found this forum to be the most down to earth. Some of the BMW forums breath some pretty rare air......

Larry

I joined that forum when I bought the car but sadly it hasn't been a whole lot of help. I think this frum has ruined other forums for me

[evan_flatt69]

So do you think I should take the head to an expert and see what's going on with it abd how much it would cost to get it in new or better condition? I'm thinking that that is pretty much my only option.

[Ranchero50]

I think you should use a rag and an air gun at the intake and exhaust port to see if either is bent. Remember, you have the head off because you have low compression in that cylinder. So it's valves, spark plugs, piston rings or head gasket not sealing correctly. With the piston at TDC can you rock it back and forth?

As far as an expert goes I would be very leery of your average domestic or racing machine shop.