BMW knocking

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I have a 90 535i I am working on for a friend. It blew a head gasket so I tore it down for a top end rebuild. The head was warped so I had it shaved and all else seemed fine. I just got it back together and it has a knock(it didnt before I tore it apart). The knock sounds more like its in the top end. I took the coil wire off and turned it over several times and no knock is audible. My main question is what and where are the timing marks. The chiltons manual shows a picture of a 318bmw timing sprocket so its no help. I tried to tie off the chain and sprocket when i took it apart so it wouldnt move during dissasembly but I want to make shure its in time. Thank you for any help you can give.

posted by  mustangmaniac

any of the pics i have are all crap, but the huge ass CAUTION CAUTION CAUTION is a tip off, if youve buggered the timing , you probably broke or bent something, sorry can't be of help. pay me now or pay me later. good luck dude

posted by  BanffAutoSpa_ap

anyone know what kind of cylinder pressure I should have. I only checked the number one cylinder so far but it was around 90 psi. Thanks

posted by  mustangmaniac

i think you should be looking for variations between cylinders as opposed to a specific pressure, because the pressure is subject to the camshaft configuration, compression ratio, and overall condition of the engine. the lowest cylinder pressure should be at least 70-75% of the highest cylinder reading. as for the knock-- did coolant get into the oil? if it did, and it was run for a while that way, the bearings could have been trashed by the viscous, acidic mixture.

posted by  dodger65

No, the oil was changed quickly after the blown head gasket.

posted by  mustangmaniac

i guess i really meant- was it driven around a bit maybe before the head gasket became apparent as the reason it wasn't running right?

posted by  dodger65

I dont think so. the car was warming up one morning when a hose blew. appearently from pressure. the next day the first thing I did was drain the oil to see how much metal was in it. the oil was perfect, no metal and no water.

posted by  mustangmaniac

any chance the timing chain tensioner is not tight enough allowing chain deflection hitting guide's is it a loud knock or tapping tick no luck on the timing marks need to know the size of motor 4 or 6 cyl ? m3 m5 m6? i could find only info up to 1988

posted by  osborste

Thanks for the advise. All I know is its a 6 cyl. Where can I find the m3 m5 m6 designation. I took the tensioner outwhen I took the head off and when I put it back it seemed to tighten up like its suppose to.
It sounds more like a light knock and sounds like its up high. I am affriad to run it for very long in case its serious. Ill be leaving for the weekend so if anyone posts to me I will check it late sunday night. Thanks again for the help.

posted by  mustangmaniac

a light knock under valve cover? if so did you adjust valve to rocker clearance

posted by  osborste

maybe a loose rocker arm, or whatever those bmw's use.

nevermind read above.

posted by  carls47807

This was my first thought. Not to sound dumb but, honestly didnt think this was an easy adjustment. I thaught it had to be done at the machine shop. Im going back to the garage now to look at it.

posted by  mustangmaniac

You had it shaved... How much?

posted by  DodgeRida67

bmw means burn my wallet.the 535 stands for yah you got it 3.5 litre.
usually 3496 cc type stuff ,of course popping heads is goot for biz.bavarian motor works originally an airplane engine manufacturer.the m5 has a much different engine and if the owner had one he would know.the front grill and back end are different,so is the exhaust.a month ago we got in a pissing contest about things like torque wrenches.now you know why you do not find calipers hanging off cars at mercedes.good luck with the damage.if the head was really warped,yikes..all that tough aluminum

posted by  the lobster

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