Cracked Head. Apparently more common than I thought.. Advice?

[Marc07726]

1997 E36 convertible.. 230K miles on it. Started blowing coolant out the tailpipe. I pulled the head, and could see Cylinder 4 had the signs of being steam cleaned. Inspected the head, and found a crack from the cooling passage all the way to the exhaust valve.

Spent the past week or so looking at options. Replace the head? Replace the engine?

Local yard had an engine, but they lied about the mileage by 2X, and the engine has been exposed to the elements in the yard for a long time.

Missed a cheap local head on EBay (kicking myself).

I don't want to be stupid and put too much money in to the car. I do like it, and want to keep it, but it is by no means "mint". If I can get it back on the road for under $800 (in parts, I do labor), I'd like to do it. That rules out any "rebuilt" parts, so I have been focused on good quality used parts.

Any suggestions?

[hakentt]

Yes, very common, these heads crack when overheated. Best option is to get good used non cracked head, it won't crack if it is not overheated. Some shops offer repair and weld the crack, don't go for a weld.

[strayts]

I'd be shocked if you couldn't find a decent M52 head for under that. Heck, you could get a decent junkyard motor for that, and a swap would honestly be less work.

[MisterM52]

throw the crackhead out..

get yourself a new motor and service it well, specially the cooling system..

[5SpeedGangsta]

Check craigslist. I was able to find a remanufactured head still wrapped up in the box along with the gasket kit and a brand new radiator for $400. The shop had ordered the parts for a customer who decided they weren't going to get the work done so they had just been sitting around for a couple years. There were also a couple complete engines on CL that for not much more.

[flyfishvt]

I have a lot of experience with this. Keep in mind if you buy a used head you'll have to get it tested and decked flat. You really should get a valve job at the same time

Used head $250
Testing etc $250
Valve job $75

These are ball park numbers but they should be pretty accurate. So with a used head you're into it for about $600 unless you get a really sweet deal on the used head. Add a head gasket kit onto that total so total out of pocket is about $750. If it turns out the head is damaged/cracked you have to pay extra to get it repaired or try to sell it and find another. Used parts are a crap shoot.

Another option is to get a used engine that's already assembled. Those will run $300-500 depending on mileage. The down side is you don't know the condition of the engine until you try to start/run it.

A third option is to get a reconditioned cylinder head from Autohead Performance. You'll get a fully tested and decked head with new valve stem seals and a valve job. It comes with a 1 year unlimited mile warranty. Their prices are pretty reasonable considering you get a cylinder head that's 100% ready to drop onto your engine. You have to send your head back to them but they pay for that. They charge $640 for the head plus $45 shipping if you can't pick it up plus a refundable $100 old core charge. Once again they pay to ship the old core back. I used them last year when I needed a head for my m3 turbo project. You still need a head gasket kit but you're getting a guaranteed head. They specialise in BMW heads.

Unlike Hackentt I don't have a problem having a cracked head welded. The key is to find a shop that warranties their work and has experience with BMW heads.

[hakentt]

Unlike Hackentt I don't have a problem having a cracked head welded. The key is to find a shop that warranties their work and has experience with BMW heads.

Lol. How good is the warranty if I have to do the job again? Lots of shops warranty their work and swear with life of their kids. But when you return and claim warranty, they quickly blame you for overheating the engine, etc.

[flyfishvt]

Lol. How good is the warranty if I have to do the job again? Lots of shops warranty their work and swear with life of their kids. But when you return and claim warranty, they quickly blame you for overheating the engine, etc.

Theres always a chance of the welf not working. That's the chance you take getting the head repaired instead of spending more to replace it. It's still a viable option. Just find a shop that has a reputation for doing quality repairs. Do your homework.

[BlueDevilM3]

I am in the same situation in my 95 with 203K. I pulled the intake manifold off last night and coolant is pooled on top of intake valves of cylinder 4. Im for sure considering Autohead Performance, which flyfishvt recommended. I have heard only good things about them.

OP, basically we are looking at ~$700 for the head after shipping, ~$200 for a gasket set and $50 for head bolts from Autohausaz. While everything is apart and easily accessible, I would think its a good idea to replace knock sensors, cam sensor, change any vacuum lines and hoses, etc. Im thinking it will cost ~$1500 in parts.

[JDStrickland]

I'm with flyfish, there's nothing wrong with welding the crack shut.

[66 6]

I sell running 98-99 M52s for $400. Why not pick up a whole engine and do what you please.
PM me if interested

[fishinrod]

One quick and easy solution is to get a bottle of block seal. The best product on the market is called Irontite. Used by many professionals. Cost of bottle should be in range of $12.00-15.00. Follow the directions and see what happens. I have used this on a cracked block on my boat and managed to get another 5 years use out of it before replacing engine.

[snaponbob]

Yes, very common, these heads crack when overheated. Best option is to get good used non cracked head, it won't crack if it is not overheated. Some shops offer repair and weld the crack, don't go for a weld.

You were doing fine until you said "don't go for a weld". Properly done, a weld will last forever. Buying a used head is a crap shoot because it will be an unknown. I have had over a dozen heads welded over the past 4 years and the ONLY one that was a problem had four cracks. YES -- four. Just too many. One or two are fine (depending on locations).

That said, at 230K miles, the rest of the engine could be "going soft".

I live in the KC, Mo. area. "Refreshing" a used E36 6 cylinder head (cleaning, testing, shaving, and a valve job) runs about $300. With a single crack the tab is $425, and two make it $475.

So, with all that said, the OP needs to establish the cause (only one -- overheating) and resolve it (completely replacing the entire cooling system) so as not to have a repeat.

- - - Updated - - -

One quick and easy solution is to get a bottle of block seal. The best product on the market is called Irontite. Used by many professionals. Cost of bottle should be in range of $12.00-15.00. Follow the directions and see what happens. I have used this on a cracked block on my boat and managed to get another 5 years use out of it before replacing engine.

Ummm ....... no.

[flyfishvt]

Used by many professionals.

Please list some of these professionals. I want to stay far away from them.

[Conley535ix]

I'm new to site I'm having problems with my heat can anyone help me it's giving a lot of codes.9C5D,9C61,E706,9C5C,9C58,9C59,9C5B,9C49, them are all the code

[snaponbob]

I'm new to site I'm having problems with my heat can anyone help me it's giving a lot of codes.9C5D,9C61,E706,9C5C,9C58,9C59,9C5B,9C49, them are all the code

What model car, and what scan tool generated those codes?

- - - Updated - - -

Please list some of these professionals. I want to stay far away from them.

Indeed. This pissing match has been played many times. On E36s this can be a disaster. Block sealer will not "repair" a cracked head. Patch it for a while? Maybe. As for "professionals"? Ha.

[E36328Coupe]

the OP needs to establish the cause (only one -- overheating) and resolve it (completely replacing the entire cooling system) so as not to have a repeat.

Not necessarily. Can be just too many heating cycles, or the casting was never flawless in the first place, and that overheating that people think caused the crack...............sometimes the water has gone through a crack and caused the over heating.

[snaponbob]

Not necessarily. Can be just too many heating cycles, or the casting was never flawless in the first place, and that overheating that people think caused the crack...............sometimes the water has gone through a crack and caused the over heating.

VERY doubtful. That really is a reach.

[tmswell]

Flyfishvt has a point, so does Hakentt -- all things considered, the milage on the car, if it was in the 100k realm, I'd say get a resurfaced/finished head that's been tested/warranted --did that for my e39 and glad I spent the $429. it was well worth it and a great buy (Guy i picked it up from was down in Los Angeles -- I think he even has a shop on eBay).
Anyways, with that high of miles, might not be a bad idea to have someone fix the crack, if you see 400ish bucks not worth it.
IMO,
- short term solution, have the crack fixed.
- long term solution, get a tested/warrantied head.

Best of luck!

[snaponbob]

Any responsible shop that rebuilds heads will warrant their work. If not --- wrong shop. The single M52b25 head I had trouble with was handled by the shop that repaired it. It was a rare failure, he paid me for my time, grabbed another head from his "pile", fixed it, and three years later the car is running fine.

[tmswell]

Any responsible shop that rebuilds heads will warrant their work. If not --- wrong shop. (...)

[E36328Coupe]

VERY doubtful. That really is a reach.

Not at all. People often think the symptom is the cause where really something had to cause the symptom.

[snaponbob]

The cause of a cracked heat IS the heat cycles you mentioned, but not normal heat cycles. It's OVERHEAT cycles that cause the cracks. And ONCE is enough. When BMW went from 12 to 24 valves, cracked heads became an issue because the simply was not as much metal in the heads. The word "fragile" is appropriate. It is an issue that practically is rarely discussed in the M20 world, and they can overheat as well. People can believe what they wish, but heads crack from abuse, not use.

[E36328Coupe]

The cause of a cracked heat IS the heat cycles you mentioned, but not normal heat cycles. It's OVERHEAT cycles that cause the cracks. And ONCE is enough. When BMW went from 12 to 24 valves, cracked heads became an issue because the simply was not as much metal in the heads. The word "fragile" is appropriate. It is an issue that practically is rarely discussed in the M20 world, and they can overheat as well. People can believe what they wish, but heads crack from abuse, not use.

If I hadn't bought my 328 at 123,000 miles and used it up to 208,000 miles so I knew it had not been cooked in the last 85,000 miles at least before it blew all it's water out with presumably cracked head, as the head gasket was perfect on removal, and THEN overheated due to the loss from the PRE EXISTING issue, which caused the coolant loss, I might be more inclined to have a less open mind on the subject.

I would agree they are a lot more fragile due to less material as you say, but sometimes things just go, not everything is made perfect. More often than not people probably do kill them through neglect but not always

[flyfishvt]

If I hadn't bought my 328 at 123,000 miles and used it up to 208,000 miles so I knew it had not been cooked in the last 85,000 miles at least before it blew all it's water out with presumably cracked head, as the head gasket was perfect on removal, and THEN overheated due to the loss from the PRE EXISTING issue, which caused the coolant loss, I might be more inclined to have a less open mind on the subject. I would agree they are a lot more fragile due to less material as you say, but sometimes things just go, not everything is made perfect. More often than not people probably do kill them through neglect but not always

During all that time between 120,000 and 200,000 did you have to add coolant? Let's face a few facts. On a healthy engine you don't add coolant more than once a year. It's not uncommon to own a car for 5 years and never add coolant. The fact is we think adding coolant is normal for these cars. It's not. Do you think the person who paid $35,000 for this car 20 years ago added coolant every month or two? I drive cargo vans for work that have 300,000 miles. We don't add coolant. If you're adding coolant every month or two months or 6 months it indicates a leak. Yes, it could be a loose hose clamp or leaky heater core. All I'm saying is you bought a car with 120,000 miles. You can't possibly know what happened to that engine before you owned it. A single overheat event is all it takes.