Just bought M42, what should i do before putting it in?

[///Harlis]

Hi everyone

First post! i only got my M42 Wednesday. It is going into my e30 318i 4dr. Anyways what i was wondering is what i should do before the engine goes in that is a MUST. I would rather work on it outside the car as its a heck of a lot easier. I noticed a bit of a leak near what i am guessing is the notorious profile gasket. So this is what i was thinking:

1. Gaskets, head, profile, timing chain case etc
2. hydraulic lifters
3. timing chain and tensioner.

The engine has done 140,000 Kms. Which is pretty low by me. Speaking to the previous owner its obvious he drove it hard, however he took good care of it (regular oil change etc). SO... pretty much what im asking for is advice on what is an easy MUST DO tune up before i chuck it in my e30. I dont like the sound of my M40 as it sounds like a sewing machine. I want this engine to sound better. Am i going to be disappointed?

thanks in advance, and heres a pic of my leak. Is it the profile gasket?



sorry for the small photo

[swiss318is]

:Di would tear the engine apart and build it up using new gaskets, bearings, timing chain etc..!full machined block...etc. no performance parts if not desired.. just to have a nice and "new" engine! you said that the previous owner drove it hard.. so be carefull! i would do a rebuild, just to avoid to transplate the engine twice..
i dont know about your budget, but you still have an engine in your car.. so dont hurry, take your time... you will have much more fun afterwards!

and WELCOME TO THE FORUM!!!

[Philip_pl]

- complete valvetrain service, ie: chain, tensioner, guides, maybe sprockets etc, consider also replacing valve seals (depends on their condition)
- replace vacuum hoses, they are old and might leak - it can cause issues with idle running for instance
- leaking gaskets - possibly oil pan gasket?
- of course all filters and regular service stuff


Of course complete rebuild including piston rings, bearings, block machining etc. is a cool thing but it's expensive and takes time.
I wouldn't touch head gasket either unless its broken.

[///Harlis]

thanks for the advice, i dont think its in my budget to do the bottom end though. If i have to do the profile gasket wont i be taking the head off? i really dont want to have to take the head off lol. all the valve train, chain, tensioner etc i will do though.

also, the engine being out of the car means it is relatively empty of oil. Wont i have to fill the lifters with oil before i put them in? Then if its another day or so till i get the engine IN the car, oil might have drained out of them right? I dont want them to seize up when i start the engine. Is there a safe way to do this? My brother suggested soaking them in oil for a few days.

[Cobra Jet]

There is a thread or an online "how to" for replacing the profile gasket without removing the head, however, I'm not sure how well this procedure really works.  I don't see how the profile gasket could be replaced and correctly sealed when not removing the entire head...

As for an engine that has sat for a while w/o being started, do the below procedure:

1) remove the spark plugs

2) get WD40 or Marvel Mystery oil and you will want to squirt a decent amount of oil directly into the cylinders (via spark plug holes).  You DON'T want to fill up the cylinders, all you want to do is just get enough oil lubrication in there to avoid a completely dry "start".

3) fill the engine w/ motor oil (get the cheapest 10w40 oil out there from WalMart, parts stores, etc - no name brand stuff, because you will only be draining it shortly and there is no sense in putting in expensive oil at this time)

4) once you have filled the engine w/ engine oil, you will want to either:

A) manually turn the crank:
You can manually turn the crank when the engine is on an engine stand or engine crane.  You will have to brace or "lock" the flywheel.  Once you have done that, get the proper size wrench that will fit onto the harmonic balancer (crank) bolt.  Once the wrench is secured to the bolt, manually turn the crank.  Do this a quite a few times as what you are doing is "priming" the engine because by manually turning the crank, oil is being pumped throughout the engine again.  IF the engine is in the vehicle already - REMOVE THE (+) BATTERY CABLE from the battery AND place the car in NEUTRAL!  You can still manually crank the engine over at the crank w/ a wrench by doing it from below if the vehicle is on a lift or if it is up on ramps and you have enough clearance to do so.

OR

B) "bump start it" (providing engine is installed in vehicle and coolant level is good):  
To do this, unplug your CPS (crank positioning sensor). The end of the CPS plug is located on the driver's side of the engine.  There is a large black connector box under the upper intake close to the side of engine block w/ (2) like plugs, one is for the CPS sensor the other is for the cam sensor (they are both black plugs).  The BOTTOM plug in this junction box will be for the CPS.  UNPLUG the CPS.  Once the CPS is unplugged, hook up the (+) battery cable.  REMOVE ANYTHING AND ANYONE FROM THE FRONT OF THE VEHICLE IN THE EVENT YOU DID NOT UNPLUG THE CPS.  MAKE SURE CAR IS IN NEUTRAL AND WHEELS ARE CHOCKED (or parking brake is applied).  Turn the key as if you are starting the vehicle.  The vehicle SHOULD NOT & WILL START if the CPS is unplugged - however the engine will automatically crank over as long as you are keeping the key held to the start position.  Do this a few times to get the oil pumping throughout the engine.

Now assuming the engine IS completely installed, has the proper fluid levels and is ready to go:

5) Once you have either manually turned the crank or used the bump start method and the oil has been circulated throughout the engine, now start the car.  Let the car run until it reaches normal operating temps.  While it is running, listen for any abnormal noises coming from the engine (there really should not be any if the internals are in good condition and the timing components are not severely worn).  If the vehicle can be legally driven, drive it for a few miles and monitor coolant temp and listen for ANYTHING that could be engine related.

6) after the engine has run for a bit (and has been driven a few miles) and the engine is determined to be in 100% operating condition with no issues, DRAIN the oil out and remove oil filter.  Install new oil filter and fill with your favorite (best brand or most expensive based on preference) 10w40 oil.

DONE.

(oh - soaking lifters in oil is not a bad idea, however, lifters will "pump up" w/ oil once you do the above.  The oil pump will circulate oil to all appropriate components.)

 

[///Harlis]

Very good to know! i'll probably print that out when im doing it lol. The WD40 will just be burnt off i suppose. Alright, thanks for that. do you have any idea on whens a good time to do the hydros in this whole procedure? im thinking just do them last before putting it back together, then fill it with oil. THEN put it in.


cheers

[Cobra Jet]

WD40 will be a non-issue, as it will lubricate the cylinder walls especially if the engine has been sitting for quite some time.  WD40 will not cause any issues or harm - same holds true w/ the Marvel Mystery Oil.  You want all of the cylinder walls to have oil on them before manually cranking the engine or starting it.

As for the lifters or "hydros", you can soak those at any point you wish to do so.  They don't really need to soak long at all, just leave them sit for about an hour or so.  Like I said above, once they are installed and you get the engine oil pump to pump oil throughout the block, they are (and should) pressurize and oil will (should) pump through them in a normal fashion.