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Lightning fast egg :)
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Discussion Starter · #1 · (Edited)
Cylinder head set-up I have finished my cylinder head and since I changed the valve guides and reground the seats, I need to have the valve lash clearance measured/confirmed.

Is this something I can do myself with feeler gauges?

The machine shop that did the work on the head for me, said they set it up as best as they can, but are not 100% sure it it is correct. At least they're honest.

What should I do? Do I get out the dialer indicator and check to make sure that the rocker arms are not on an angle. If they are then get the feeler gauges under the shim till rocker arms are perfectly parallel?

Any help is appreciated! :confused:

TIA
 

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i am no mechanic but i am rebuilding an sr in auto class. after my valve job the teach told me to take off about 70% of the total taken from seat and face off the valve tip the hydro lash adjusters should take care of the rest. someone correct me if i'm wrong.
 

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Once its all setup , you can check it with a feeler guage or with a dial indicator , It should be zero +/- .0010in. clearance !!!
 

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Lightning fast egg :)
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Discussion Starter · #4 ·
The machine shop said they took about 4 thou off the valve seat and couple of thou off the valve stem end, to compensate. They think they've got it close, but do not know how to measure/verify properly.

Here is my theory:

If the valve stem was too long (shim too thick) then the valve would not seal properly and would leak. Right?

It the valve stem was too short (shim too thin) then there would be too much clearance and the rocker arm would make noise. Right?

Again any help/thoughts are appreciated.

Thanks for your input sr20dereamin!

PS: Should I take it too the local Nissan dealer to have it done?
 

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Lightning fast egg :)
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Discussion Starter · #5 ·
I assume the checking should be done with the cam in place right?

SHAWNATGERBROCK said:
Once its all setup , you can check it with a feeler guage or with a dial indicator , It should be zero +/- .0010in. clearance !!!
 

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Yea, cams in place , just crank the engin eso the cam lobe is up , either use a dial indicator or if you can find a .0010in feeler guage , check between the rocker and the valve , the clearance should be between 0 and .0010in. ....If it is to tight , it could burn a valve if left to long , if its loose it will be a little noisy ....The dealer has different thickness shims to make it right , figuring out the correct shim is the fun part ... you will need a FSM for that, It would take forever for me to explain it ...Basicly there is a mathmatical formula you use , take the clearance and the shim that you have and do a formula and it gives you the correct shim needed ....
 

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Lightning fast egg :)
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Discussion Starter · #8 ·
SHAWNATGERBROCK said:
Yea, cams in place , just crank the engin eso the cam lobe is up , either use a dial indicator or if you can find a .0010in feeler guage , check between the rocker and the valve , the clearance should be between 0 and .0010in. ....If it is to tight , it could burn a valve if left to long , if its loose it will be a little noisy ....The dealer has different thickness shims to make it right , figuring out the correct shim is the fun part ... you will need a FSM for that, It would take forever for me to explain it ...Basicly there is a mathmatical formula you use , take the clearance and the shim that you have and do a formula and it gives you the correct shim needed ....

I've got the FSM and understand how to figure out the shim thickness. The hard part is taking the measurement with the proper dial indicator that is put in place of the Hydraulic Valve Lash Adjuster. Have you tried using the feeler gauges? There isn't a lot of room to try to get one in there. I'll give it a shot tomorrow. Thanks.
 

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nx2k-boosted said:
I've got the FSM and understand how to figure out the shim thickness. The hard part is taking the measurement with the proper dial indicator that is put in place of the Hydraulic Valve Lash Adjuster. Have you tried using the feeler gauges? There isn't a lot of room to try to get one in there. I'll give it a shot tomorrow. Thanks.
how did it work out? what did you end up doing?
 

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Lightning fast egg :)
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Discussion Starter · #10 ·
Well, it didn't. I put it together and the drivetrain is noisy. The car's been sitting as I haven't had the time or motivation. I still need to get it shimmed properly. I only had a 0.002" feeler gauge and since it didn't fit in I figured the gap must be pretty close. No way Jose. The valve train is VERY noisy and the idle is all over the place. I figure if it was the Hydraulic Valve Lash Adjuster it would go away once the oil pressure builds up, but it didn't. The rattling does go away under load though. I've lost my motivation, which is too bad, since I'd love to be driving the car.
Any tips boys?........or girls :)
 

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thats too bad it seems like no one messes with it here. Only place that advertises it is jgy but you have to shipped your head to them...

I would like to reshim both of my cars but I don't want to disassemble them to do it. They are a little noisier than before but not too bad.

on the g20 I got a new head but w/o shims so I used my old ones and the 240sx I think the shims were switched around..every once in a while I'll get a clacky noise at idle.
I cant find a place the does sell the kent-moore tool either...
 

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Lightning fast egg :)
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Discussion Starter · #12 ·
What I don't understand, is when people get new heads how do they go about it? You can't just use shims from an other engine, since they're all different. I bet you, no engine has the exact same shims. I thought about JGY, but I'm not taking the head off for that. If anything I'd set something up and drive down there and get it done with the head in the car. The other thing is that none of the local Nissan dealerships have the dial indicator with the attachment as per factory manual. I though of getting a T-vernier and using the top surface of the head as the base point. I hate doing things half assed, especially when we're talking such tight tolerances. Too bad our engines don't have individual hydraulic valve lash adjusters like the WRX engines. Nissan cheaped out on that.
 

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Men the sr20 come with hydraulic lash adjuster, if your valve train is noise , maybe your HLA got air. To bleed you have to remove and put in oil, with a small pin or drill bit insert on the hole of the Hla and bubles will come out.

How you know if you Hla´s got air, push them down, if they compress like 1mm or like 1/32 inches got air, thean check clearances of the shims and guides.
 

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NewSR20. said:
Men the sr20 come with hydraulic lash adjuster, if your valve train is noise , maybe your HLA got air. To bleed you have to remove and put in oil, with a small pin or drill bit insert on the hole of the Hla and bubles will come out.

How you know if you Hla´s got air, push them down, if they compress like 1mm or like 1/32 inches got air, thean check clearances of the shims and guides.
this is not noise hla its not that loud, HLAs with air sounds like a loud tapping. this is a little different. Besides I've already bled both sets of mine so I know thats not it.

we both know the sr has hlas...all he was saying is why doesn't the sr have 1 per valve like many other motors.
 

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Discussion Starter · #15 ·
I bled all the HVLA before I reinstalled the engine. Keep in mind that there is one HVLA for two valves. If one valve shim is too thin or thick it might result in noisy valve train. That's might theory anyways ;)
 

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Discussion Starter · #16 ·
Bump

A year later and the car is still sitting in the garage with the noisy valve train. Anyone have any suggestions? Winter is almost here so I'll have plenty of time to work on it :rofl:
 

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O.k., you have 2 HVLAs and 2 valve shims per rocker arm. Because you will/can have 2 different length valves while using one rocker arm, you need to make sure that both valve shims will be the same height so they will be even when the one rocker arm is riding on them. The tool that Yahnoza(Pat) has is a good one. You can also get one that is Nissan specific which has a plate that bolts where the cam caps bolt, that has 4 holes through it so you can do 4 valves at a time. With this tool, you will also use a dial indicator. Pat's tool is good and considerably cheaper but I think that the Nissan tool is much more accurate because it is bolted to the head. In no way am I trying to knock Pat's tool. If I didn't already have a Nissan one, I would buy his.

You def. need to get this done or you could have something bad happen.

My .02
 

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Hmmm. Well I know I didn't do this when I built my engine. :redface:
 

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Lightning fast egg :)
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Discussion Starter · #20 ·
Thanks guys, that's exactly what I need! I went to three local Nissan dealerships and they did not have the Nissan tool. There is hope afterall :)
 
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