1988 BMW 325i Convertible motor condition question

[dworthy]

Yup, that's what's left of a rocker, noticed the date stamp of "85", not the first time this head has been off.

[PEZ2]

Interested in pics of pistons when you get the head off. Don’t forget there is a head bolt loosing sequence, sometimes it’s forgotten. I am waking up a 12 year stored 325i coupe. I did a engine prelube before startup. You may want to consider oil the piston rings and upper cylinder walls prior to reinstalling the head. My 325 runs but injectors are crap.

[82eye]

here is the pic--not sure if it attaches
Attachment 708325

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i will try to pull the head the next day or so

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that's a snapped rocker. they are the weak point, so the valves don't go right through a piston or eject up through the head when a belt breaks.

you will need to have the head refurbed or replaced. there are gonna be valves bent or broken as well as the rocker damage. check the cam lobes for scoring as well. if you fix it this would be a great time to upgrade the rockers and cam, or have the cam reground.

edit : if you have a donor car for the 5 spd, your cheapest option would be pulling the head from the donor and installing in on the other. if not the whole engine.

Yup, that's what's left of a rocker, noticed the date stamp of "85", not the first time this head has been off.

you have great eyesight. i am jealous.

[markbimmer]

is it best to remove the bolts from the manifold or the two pipes near the manifold --in order to remove the head? if any tricks of the trade please pass them this way. i have sprayed the nuts and bolts with PB blaster---just have a fear that they will break off when i try to remove them--which i guess is normal for them to break?? thanks mark

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wow really--i didnt even notice---85---u do have good eyes

[markbimmer]

i do have a donor car that i am refurbishing so i guess it is not a donor car now lol--it has a strong (i think) motor and 5 speed transmission. when i bought it--i had no idea the condition of the engine or transmission, I bought it for a parts car -but decided it refurbish it--it was missing the rear diff, head lights, cluster, cat, and other parts---so far i have replaced most of the parts--and i like that it is a 5 speed. So, i really want to try to rebuild this one with engine problems. I have never gone deep into an engine and I'm 60 years old. it has always been in my bucket list to rebuild a motor. So now i have 4 -1988 e30s----3 convertibles and 1 sedan. I'm enjoying the challenge--and thanks for lots of help here and youtube.

[PEZ2]

To answer your question ( two posts up ) I have removed lots of m20 heads and have concluded that removing the head pipes from the manifold was easier for me. I was able to work manifold to head bolts on the bench with more success. That’s not to say you can’t pull the manifold from the head in the car.

[markbimmer]

Thanks Pez2-from my view that seems the best way also just looking at the 2 options.

[82eye]

you can remove the head with both intake and exhaust manifold still attached. it is often easier to remove the manifolds afterward, though i'd be prepared to cut the exhaust bolts off, exhaust manifold nuts rarely make it off the car unscathed and will need replacing. you may also need to replace some studs.

the intake * should * remove fairly easily off the car.

[dworthy]

I have done it both ways, if you are going to be taking your time, and pulling the motor anyway drop the exhaust after the manifold and pull the engine with the intake still attached. Leave the P/S pump and A/C in the car so you don't have to drain them.

Pro-tip: Mark the location with paint pen where the hood hinges attaches to the hood, makes it much easier to align. Also just disconnect the washer pipe at the pump and pull it with the hood.

[markbimmer]

Thanks guys--i appreciate the help and suggestions. i spent the afternoon today-on another BMW---finally got the rear hub and bearings out and replaced the bearing and e-brake shoes on one side. I will get back on the one we are discussing soon. maybe tomorrow afternoon i can work disconnecting the pipes next to the manifold. thanks on the hood --i did mark it--all three of my convertibles have the hoods off right now lol. I dont know how anyone can do work on these BMWs with the hood on--I've already changed the timing belt, and replaced water pump on the other two convertibles--as well as all belts and hoses and thermostat. Once i replace the other wheel bearing and e-brake shoe---this little red convertible will be road ready. On this BMW --i've already replaced rear shocks and front struts--control arms and tie rods as well as all belts and hoses and plugs, brake line hoses, calipers and pads.

[goinstrong]

LoL my wife’s ‘88 vert has a dent in the exact same spot on the passenger front fender!!


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[markbimmer]

really-for me it was like this when i bought it---do you know how the dent got into your wife's car?

[markbimmer]

i havent pulled the head yet--but i suspect valve damage--i think was on target

[markbimmer]

i pulled the head finally. there was a broken valve on top of one of the pistons. i cant see any piston damage but maybe i dont know what to look for. I will post pics so maybe someone can view them and give me some guidance.

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thanks--i posted pics here of the head and pistons

[82eye]

nice work so far. that's a total rebuild...
think of all the fun upgrades .. i just hope the head is savable.

[dworthy]

So I would closely inspect #3 as that had valve contact and broke the valve. The rest looks to be in good shape, I wonder if it just dropped a valve and not broke the belt on that motor. Also closely inspect every piston for fresh impact marks, as much carbon each piston has, should be pretty easy. You might be able to salvage that head, and have a machine shop deck and pressure test the head.

[markbimmer]

thanks guys this gives me hope. if the head is good--would it make sense to replace the valves, rockers. Im not sure what an upgrade is on the valves, cam or rocker. what puzzled me is the broken valve came from the 3rd cylinder but when i took the head off--the broken valve was on top of the 4th piston--how is that possible? i guess the first step i need to do is check the piston to see if any damage, remove all the parts on the cam and take the head to see if it is ok or not? does that sound about right? one other question--i had no compression in any cylinder---do you think this is normal based on what you can see on the head and broken valve. Also, how do i inspect a valve to know if it is bent or not? thanks again for all the help.

[markbimmer]

i mean the broken valve was on top of the 3rd piston but it was broken on the 4th cylinder

[dworthy]

That's a bit odd, for it to do that, but then again I have seen weird things when the timing belt goes on those motors. You can always contact VAC Motorsports to see if it's worth rebuilding.

[markbimmer]

i think i was wrong again--the broken valve was on the same cylinder. i guess i need to go back to 1st grade and learn how to count. I'm taking the head to a head shop today. the shop said they will fix and replace parts--i guess that is the best for me. the shop has an excellent reputation from Mechanics i spoke with. i had one mechanic to look at the head where the valve broke. there is a small place on the cylinder that could be a crack but he was not sure. i will hope for the best. The shop charges about 300 bucks not counting the price of replacement parts installed. At least i trust the shop to do it right. the mechanic also looked at the pistons--from his view he saw no visible damage.

[markbimmer]

I cleaned the pistons and walls--i think they are good. the head shop called and left message that the head was ready to be picked up--that sounds like it was in ok condition and not salvage. they replaced needed parts. Not sure the cost of it yet. i ordered new head gasket and head bolts and manifold bolts. Since it has been sitting for 20 years--do you think it is a good idea to replace the fuel injectors or have them rebuilt while the intake is off? thanks mark

[richardodn]

Cleaning the injectors while it's apart is a great idea. Which head gasket brand are you using?

[markbimmer]

thanks for your message. when you say cleaning---do you mean like overhauling the injectors? The head gasket i ordered is a Mahler --i think that is the right spelling. I believe it is german made. do you recommend a different brand on head gasket? i know a good one is important, thanks again for your message

[dworthy]

I would send them out to these guys, for 30 bucks each they replace the o-rings, pintels and flow test them: RC Fuel Injection

Several years back I had them clean the old 318is ones, see attached.

Edit: Elring sells a headgasket kit IIRC, comes with all you need to replace, every gasket included: BMW Cylinder Head Gasket Set - Elring 11129059240 | FCP Euro

[82eye]

elring is good. there's a few injector upgrades. i didn't bother with getting my old injectors serviced. i went with a newer 4-pintle injector as it atomizes better, allows for a bit more power, and helps keep idle even. it was even suggested by a couple trusted shops. you may want to look into it.

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elring is good. there's a few injector upgrades. i didn't bother with getting my old injectors serviced. i went with a newer 4-pintle injector as it atomizes better, allows for a bit more power, and helps keep idle even. it was even suggested by a couple trusted shops. you may want to look into it.