hermonic balancer

[blackjack]

I just pulled a 280zx motor to put in my 240z. I already have the block mounted to an engine stand. The problem is I need to remove the hermonic balancer so I can replace the timing chain and sprokets. How do I stop the motor from turning to get the hermoic balancer bolt out?

Also do the rear main seals go bad fairly often on L series engines, are they like 302 motors? Another question since I have the engine torn apart this far should I go ahead and replace the head gasket as well? The head was rebuilt maybe 50,000 miles ago maybe less, well not sure on how many miles since the rebuilt head.

Thanks for any help.

[Gav240z]

The best way to remove the harmonic balancer bolt is to put the flywheel bolts into the rear of the crank and use something to jam it from moving such as a long steel pipe or spanner etc..

The rear main seal in my Z was bad and causing oil to leak onto the clutch assembly and flywheel not good so I'd replace it as to not do it would be false economy at $10 or whatever they are.

The head gasket is up to you. I've never had a blown head gasket in my Z but you never know.

[texasz]

Impact wrench if you have one or can get a buddy's.

[ZSaint]

Get a tranny bolt and a 3/4" wide by 1 1/2" long piece of 3/16-1/4" thick steel. Drill a hole at one end of the tab for the bolt. Take a hack saw and cut a 'point' in the other end of the tab. Place/bolt the tab on the upper right tranny bolt hole in the block. Turn the tab so that it enters into a tooth in the flywheel. You may have to alter the "point" a bit to get it to 'fit'. Take a breaker bar and crank away. The crankshaft/flywheel will be jammed and not turn. After you take the H/B off and want to torgue it back on, move the tab over to the leftt side tranny hole and torque away. This is kinda crude but will work for someone w/o an air wrench! I learned this trick in 1965 when I started building race engines. Still have the "tab" that I made 40 years ago and it still works great!

[Bambikiller240]

Since your engine is already on the stand, the Impact gun is your only choice to lock down the crankshaft, unless you remove the engine from the stand.

Last time I needed to do this (with engine on a hoist), I slipped the long end of a HEX wrench into one of the holes in the block used to mount the trans, and turned the short end of the wrench inward until it engat=ged the teeth of the flywheel. That jammed the flywheel/crankshaft and I was able the break the harmonic balancer bolt loose with a 27mm socket and a looooong breaker bar..

[Zedrally]

There is one other method of removing or rather breaking free the Crank bolt.

Remove the valve cover, on inspection of the camshaft you will observe a section that has 2 fin like sections. By using a large adjustable spanner or plumbers wrench you can have a friend hold the cam from moving in this way while you use a large breaker bar on the bolt. No friend available, then let it jam on the head...

MOM

[Marty Rogan]

Also do the rear main seals go bad fairly often on L series engines, are they like 302 motors? Another question since I have the engine torn apart this far should I go ahead and replace the head gasket as well? The head was rebuilt maybe 50,000 miles ago maybe less, well not sure on how many miles since the rebuilt head.

Thanks for any help.

You will never have a better time to change the seals. As long as the engine is out, change ALL of the seals. That's what I did. Should be good for another 30 years.

Marty

[blackjack]

Update:

I had the valve cover off so I used a large spanner to hold the cam in place just in case the inpact wanted to move the crank shaft. Using the impact was a very very quick way of doing it. Came right off. These L series engines are so much easier to work on compared to V8's. It's such a pleasure to work on something like this for a change.

I don't know why I didn't think of the impact wrench. Well one is I don't have a garage but I do have a compressor and a portable tank though.

Thanks again for the ideas guys.

[1GENZED]

Hey

Since were on the topic of harmonic balancers, Has anybody else heard about or done a BMW balancer conversion? I read somewhere that it used to be a quite common upgrade on our engines. I can't find anything on this topic.

Thanks,

Ahmed.

[beandip]

The rear main seal can be removed and replaced with out droping the pan . Just be careful not to scratch the surrounding surfaces or the new seal will leak. I used a seal puller for this , Nappa auto parts about $6.00 . For the future , another way to lock the engine in place . Turn the engine over untill one of the cylinders is on the compression stroke. Stuff a length on rope in the spark plug hole , if on the compression stroke the valves will be closed this is important. Now when you turn the engine the piston will compress the rope against the head and this will lock the crank in place. NOTE: leave a tag end of the rope sticking out so it is easy to remove. This works to remove the flywheel bolts as well . Jambing the cam puts all the load on the cam chain . Yeaks :dead: I don't know about doing that .Gary

[blackjack]

Is that true about the BMW hermonic balancer swap. There are a bunch of BMW's here in the junk yard in San Diego. I was looking at the Euro damper in the Motorsport magazine but didn't want to spend the money on it right now.

If anyone knows about this please chime in.

Thanks.