l20b chain slop?

[Lozer]

how much slop is to be expected on a cold motor?

[ggzilla]

None. If you can hear it, take the timing cover off and adjust the chain guide. Has it been more than a year since the chain stretch was checked?

[Lozer]

ive only had the car for 2 months. and i just did the head.

 

i can move the crank about 5 degrees each way from tdc before the cam moves.

[Cuts metal like mad]

Do you have a repair manual?

[Lozer]

yes? im hunting down a timing chain kit & tensioner now.

Edited December 24, 2008 by Lozer

[datzenmike]

There won't be any slack in the chain when running. Think of a mountain bike. As long as you are pedaling, (motor running) the tension side will be tight. The derailleur acts the part of the tensioner.

 

Check the chain stretch as per ggzilla and the manual. There are two adjustment settings to remove excess stretch. Lot of work to change to a new one if it isn't needed.

[Lozer]

im on #3 on the cam sprocket. i look down at the chain guides and they look to be adjusted all the way out. and i would need to adjust it out almost a 1/4 inch to take up all the slack.

 

This was all brought on by what i thought to be lifter noise but my lifters were well within spec.

 

Now when i would let the car decel from 4 k or so. it would make this sorta groaning whine till it got down around 1500 rpms.

 

I have to mention that the car runs friggen great aside from the odd noises.

 

so what do you guys think should i just bite the bullet and buy the kit?

Edited December 24, 2008 by Lozer

[datzenmike]

Yup.

[Lozer]

Napa auto

 

l20b timing chain kit 65.77

053-90200

[hang_510]

jap made? good price. if not-reject and try rockauto for a jap made.

 

if the tensioner and guides are good, a new chain may suffice.

 

 

i drove around for (way too long :blink: ) w/o the tensioner. everything! needed replacing but ran well enough.

[Lozer]

so when i go to install this on friday should i move the cam sprocket back to number 2?

[datzenmike]

L16/18 #1

 

L20B and NAPS Z engines #2

[datsunfish]

If you remove the valve cover and set it to tdc by hand turning it in its proper rotation look on the passenger rear side of the sprocket and it will have a v notch that should be slightly to the right of center on a dash mark on the cam tower. So long as this is correct it should run fine. Chain motors make noise and rockers and lash caps wear and will not show that you are out of spec because your feeler guage will ride atop of the wear divit.

[Lozer]

so datsunfish are you saying i don't need to replace the timing chain as long as everything lines up properly????

[ggzilla]

You don't need to replace the chain, unless it is worn out. Most likely you just need to adjust it.

 

They rarely go bad...

 

When checking the cam timing, make sure you *only* turn the engine clockwise. If you turn it back to "line it up", it won't read correctly. Turning clockwise keeps the chain properly tensioned. But you should adjust the chain first.

[Lozer]

ok so i checked the v on the cam and the v is to the right of the - in the backing plate. i reiterate im on setting #3 on the cam and the chain guide looks to be pushed almost all the way to the right (into the chain) and i still have about a 1/4 to 1/2 in of play in the chain on the pass side.

 

Now im gonna ask clearly is this safe to drive in this condition or should i replace all the equipment under the timing cover (if im going in there im gonna do it all not just adjust.)

[datsunfish]

When its turned the right way the chain will have tension on one side and slop on the other when its not running.Extensive chain wear can allow it to skip a tooth but that would take a lot. If the notches are good its all good. Dont fear. I have had many issues with old L motors but never a problem with a chain.

[Cuts metal like mad]

some one give him the link to the Hainz video.

 

Sounds like you have a misadjusted slack side guide... Or a VERY worn guides and tensioner I'd guess the former. There is a figure 8 hole on the bottom of the slack side guide and a slot for the top hole... If one or both of these are off you'll have what would seem like a stretched chain.

[Lozer]

Ok i understand ill adjust it and see if that takes out any of the slop.

so if i were to leave it alone whats the worst that could happen? (i dont have enuf slop to jump a tooth)

 

aside from floating a valve these are non interferance motors right.

[Cuts metal like mad]

no... The pistons will smash the fuck out of the valves!

[datsunfish]

no... The pistons will smash the fuck out of the valves!

 

Are you sure about that? I think they are non interference. Pretty sure the naps is not though.

Would have to hear it run to better assume an issue. I think you are safe from chain problems but I have had a guide break apart on me before. If your marks are lined up right it should run fine. It would take a lot of stretch and high rps to break or slip teeth.

[Lozer]

Yea im just a little concerned about the vale train noise and the slop on the pass side of the chain.

[Cuts metal like mad]

yes I am positive, when assembling my l20b I turned the crank over before installing the chain (slowly of course) and it stopped half way through a revolution.

[datsunfish]

yes I am positive, when assembling my l20b I turned the crank over before installing the chain (slowly of course) and it stopped half way through a revolution.

 

Without the chain actuating the valves you would have a serious compression lock. That could cause that. I have turned a cam 360 deg. with the block at tdc and did not have any lock up. we'll see what some of the other guys say when they wake up and check in before doing the xmas thing:D

[Cuts metal like mad]

no compression with the plugs out... :D

 

Oh yeah... How could it lock up from compression if the valves are open on the cylinders it's "locking" up on? Tdc on number 1 (cam and crank) crank turned over half (so 1 and 4 go down 2 and 3 come up and stop)... And number 1 is the only cylinder that has both valves closed... It's able to down but not come up in a single rotation? With the plug out?nope... That's not it... 2 and 3 clearly had have been hitting the valves that were open.

Edited December 25, 2008 by zuum510