engine and drivetrain how can you keep timing chain in place while removing head?

[royrodgers123]

i need to know if there is some trick to maintaining the chains placement while pulling head? so that i won't have to take engine apart more.

thanks in advance

mike

75 bmw 2002

[2002]

Set the engine to Top Dead Center. Remove top timing chain cover. Remove top timing chain pulley. Then remove head. Of course you'll have to remove the intake and exhaust manifold, beforehand. Whan you put it back together set the valve train back to the same position, and put the top pulley back on the front of the cam at the same setting.

There are always a few things that can go wrong so be careful, and you will be sucessful.

One thing to consider if you are having a valve job done is that the rings may not be up to the new compression available from the newly refurbished head. You will then start to burn oil past the rings, and/or have low compression.

[TJW]

Do you mean 'how do you stop the chain falling inside the engine' if so use a bit of fencing wire, welding rod or baling twine through the chain links and hook the ends around edge of lower cover or stud or whatever is available.

[Mike Self]

Set engine to #1 TDC (not vital, but it'll help when you reinstall). Unbolt the camshaft sprocket from the cam, loop some wire around the chain so it won't come off the sprocket, then run a bungee cord from one of the holes in the sprocket to the hood crossbar (prop the hood open with a stick so it won't be accidentally closed) then remove the head.

Since the sprocket will only bolt to the cam one way, you'll reinstall it in the same position that it was in when you took it off. Worked for me...

cheers

mike

[Brandon]

Do you mean 'how do you stop the chain falling inside the engine' if so use a bit of fencing wire, welding rod or baling twine through the chain links and hook the ends around edge of lower cover or stud or whatever is available.

A wire tie works great for this too...

[jp02ti]

remove the sprocket form the head and use a bit of wire to tie the chain to the sprocket. threee pieces works well, one through each of the bolt holes, except the bottom one. it prevents you ending up just one link off when you reassemble. ask me how I know!!

it also prevents it from dropping down into the block.

Jon

[Napes]

I too used the same procedure as Mike Self - bungee cord to the hood cross tube. Worked fine. Also, might want to remember to put a small mark on the dizzy before removing, and then don't move anything on it once you've eased it outta the head. Re-install w/ the mark in line and you'll possible not have to do the in-and-out dizzy dance to get your rotor lined up w/ the perimeter mark. This also worked for me a couple of months ago.

Bob Napier

[Byron]

(nt)

[pkbinplano]

Zip tie chain to gear. Then suspend. Also leave intake, carb and exhaust manifold on the head. Pull off all at one time. Disassemble on bench. Soooo much easier. Reverse order to assemble. Assemble on bench then set the assembly on block. Sooo much easier . Just did it. More quality control this way.

[fahrvergnugen_02]

It was always much easier to remove the head from my audi turbo with manifolds/turbo still attached, and then disassemble on the bench. Unless you've got long head studs or have an engine that fits very tight into the engine bay, removing the head with most/all of the ancillaries attached is always going to be much less of a headache. It's also an easy way for technicians to beat the "flat-rate" time on removing a cyl. head that needs to be machined or rebuilt. ;-)

Wire tie-ing the chain to the sprocket is a good idea...people working on these engines should keep in mind that chain and sprockets have a very specific wear pattern, so it's best that they're all kept meshed together even during removal of the head and/or camshaft. Not absolutely vital, but I guarantee it'll ensure longer life of the chain drive assembly.

Cheers!

[mzrj]

Im about to do this job as well. Is there any chance that when removing the chain the chain tensioner will shoot out and fall into the oil pan?

[blue7500]

It's got a little enclosure, so unless you really, really convince it, it should stay.