Should I replace the motor?

[rccardude909]

Hey guys I would really appreciate if you can help answer some noobie questions. I just bought a 1989 325i manual. The odometer stopped at 240k but there was not many more miles clocked on it after that since it was in storage for 3 years. The motor is strong and seems healthy other than the fluctuating idle. I was going to replace the head bolts and the headgasket. I wasn't going to do a rebuild but just a head refresh to check for cracks, valve grind, valve seats, deck for straightness, etc and change all the seals. Would it be advised to just swap in a lower mileage m20 engine. I'm a college student so I don't have the money to do crazy strokers or anything. Your help is greatly appreciated.

[whiltebeitel]

I wouldn't worry about it too much. It sounds like you may need to clean out the AFM and see if the ICV is going south, but the engine itself should be fine. The M20 is known for lasting a long ass time.

[strad]

I'm a fan of leaving things alone if they're working properly. Have you checked compression/leak down? If good leave it alone.

Hopefully obvious that you should replace the cam belt though.

[winstontj]

Out of curiosity why would you replace the head gasket or head bolts?

[rccardude909]

I thought it was general consensus that the head bolts had to be changed to the torx style? If i have to do that then I might as well do head gasket at the same time. Yeah all the belts and maintenance items will be changed for sure thats why I've left the car sitting there, I'm scared of the belt snapping on me. I have not done leakdown or compression yet but will be getting it done once summer starts. Thanks for the responses guys..very helpful

[strad]

Your car originally came with the Torx style. Does it not have them now?

[rccardude909]

You know what I actually havent checked. The car has just been sitting there since I got it. I figured 250k is almost due for a headgasket anyways. I drive >100 mile trips pretty often so it would be nice to know that it wont blow on me.

[fwappy]

Water pump, timing belt and tensioner, yes! Head gasket, no way.. unless there's an oil leak or air getting into the cooling system. I would just change ALL the fluids: oil, coolant, MTL, diff, etc... and air filter.

If you are feeling adventurous, I'd clean the fuel injectors and replace the fuel filter, too.

[rccardude909]

Ok cool thanks. I have everything you mentioned already sitting in my room. I will check the coolant for traces of oil when I drain it. It was my notion from reading online that a headgasket problem could slowly develop over a long time and eventually randomly blow. Is there anything to be worried about since the car does have 240k? Thanks a lot.

[fwappy]

Ok cool thanks. I have everything you mentioned already sitting in my room. I will check the coolant for traces of oil when I drain it. It was my notion from reading online that a headgasket problem could slowly develop over a long time and eventually randomly blow. Is there anything to be worried about since the car does have 240k? Thanks a lot.

The headgasket I guess could randomly go, but if it does, it's not like the car's going to blow up or anything. It's not like breaking a timing belt.

Just keep the cooling system healthy and that head gasket will last. When you flush the cooling system, just be sure to bleed it correctly and check up on it for a few days afterwards for more air. Keep your eye on the temp, and NEVER let it run hot. Good luck!!

[erik325i]

I thought it was general consensus that the head bolts had to be changed to the torx style?

Look under the valve cover to see what kind of headbolts are being used right now. If they are the hex style, I would simply replace them one by one. In the correct sequence, remove one headbolt then insert the new headbolt and torque to spec. Follow this procedure one bolt at a time until all of the bolts have been changed over.
This way, you don't have to replace the headgasket.

Make sure to replace the timing belt though.

-Erik

[rccardude909]

Thanks guys I appreciate the help. I'll post some updates once i see how everything looks

[e30_325es]

Look under the valve cover to see what kind of headbolts are being used right now. If they are the hex style, I would simply replace them one by one. In the correct sequence, remove one headbolt then insert the new headbolt and torque to spec. Follow this procedure one bolt at a time until all of the bolts have been changed over.
This way, you don't have to replace the headgasket.

Make sure to replace the timing belt though.

-Erik

If he has 240k on the original hex head bolts, I'd leave well enough alone. If they haven't broken by now, they won't in the near future. My 87 has 320k or so on the orginal hex head bolts, and you better believe that I am not going to touch them. If it ain't broke, don't fix it, unless you are talking about the timing belt.

[AlarmedBread]

My car was doing the "funny idle" thing too. I had cleaned/checked all the common sources, then I removed my valve cover to adjust the valves and I found the ashes of many dinosaurs in the breather tube area!!. Well, lets just say it was caked full of crap under the steel cover that is riveted onto the underside of the valve cover. The PO's of my car were not very good about changing the oil on a regular basis. Cleaning this out and adjusting the valves solved my problems.

I would not pull the head, if there was a crack, you would know it. Just keep the old girl in fresh fluids, belts and water pumps it will keep going for 250k more.

[rccardude909]

Sweet! all these replies are making me less worried. All the maintenance stuff will be done. Thanks