How will I know when I need to adjust the valve lash? Am I looking or listening for anything in paticular? Its a 97 with 155k and as far as I know its never been done.
Thanks all......
Thanks all......
Valve lash...how do I know? (1 Viewer)
- Thread starter p8nt
- Start date
This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.
The answer is that you don't know until you check them. If they are getting loose then you may hear excess valve noise, but it's such a gradual change that you will never really notice. If they are getting tight, then you will know when you burn a valve and the compression on that cylinder plummets. You wll really get to know your valves if that happens, because the head is coming off next ;(
Check them real soon, record the numbers, and then check them on a regular schedule. I like 30K miles.
Check them real soon, record the numbers, and then check them on a regular schedule. I like 30K miles.
- Thread starter
- #3
I gather from that sage like wisdom that its in my best interest to move this to the top of my "to do" list 
Aside from a feeler gauge are there other unique tools ill need? any SSTs?
Thanks John
Aside from a feeler gauge are there other unique tools ill need? any SSTs? Thanks John
The FZFE motor is somewhat different in that it uses "puck" type shims. So if one is out of spec. one must obtain the correct shim size to fix the tight or loose issue.
You will probably need valve cover gasket, and while you are in there might as well go ahead and replace the spark plug tub gaskets too. Call Cdan and get great prices on OEM parts.
You will probably need valve cover gasket, and while you are in there might as well go ahead and replace the spark plug tub gaskets too. Call Cdan and get great prices on OEM parts.
- Thread starter
- #5
How many 
's requiered for this job? Also, should I just buy a complete shim kit along with the gaskets? No telling how many will need replacing or of what size shim right...
's requiered for this job? Also, should I just buy a complete shim kit along with the gaskets? No telling how many will need replacing or of what size shim right...
I gather from that sage like wisdom that its in my best interest to move this to the top of my "to do" list
Thanks John
Apparently the valves can readily fall out of tolerance, so a farely frequent check interval is prescribed (30k as indicated above). There are two special tools needed to remove the shims (if out of tolerance), unless you just remove the entire camshafts. The FSM indicates the shims at the number 6 cylinder can only be exchanged by removing the camshaft.
This item is also on my to-do list also. For me, it appears to be a two stage process... 1) removing the valve cover, check the clearances and calculate the required shim thickness if any are out of tolerance, then button back up. 2) order required shims, remove valve cover and replace shims. Unfortunately I can't have my rig down for a week awaiting the new shims... if any are required to be changed that is.
:Beer:
Rookie2
- Thread starter
- #7
Thats exactly my issue rookie. There weather is about to get nasty and I can be without 4WD for a week! I think Ill follow your lead and do the spec, order whats needed, and then do any requiered repairs the next weekend. Do you know how many sizes of shims there are?
here is the deal. You measure the gap between the top of the valve and the cam shaft. If it is out of spec you then remove that puck and measure the thickness. Then either add of subtract the error in the gap reading and look up the needed new puck on a chart in the FSM and place an order.
The measuring device would be a caliper or micrometer, micrometer being better, There is a SST that allows you to remove the puck without taking out the cams but that doesn't work for the #6 cylinder.
So basically you need to measure and record all the valve gaps, remove the pucks and then calculate the error and needed new pucks.
I did my engine for the first time at 180k and needed 18 pucks. Dan had them coming in from all over the country. And since some were for the #6 cylinder I had to pull the cams.
At your mileage plan on the truck being down a week.
The measuring device would be a caliper or micrometer, micrometer being better, There is a SST that allows you to remove the puck without taking out the cams but that doesn't work for the #6 cylinder.
So basically you need to measure and record all the valve gaps, remove the pucks and then calculate the error and needed new pucks.
I did my engine for the first time at 180k and needed 18 pucks. Dan had them coming in from all over the country. And since some were for the #6 cylinder I had to pull the cams.
At your mileage plan on the truck being down a week.
Rick,
When you replaced the shims, was there a particular side of the range you leaned toward for the new shims? Seems like I recall there being some discussion about this (Robbie IIRC), and I think he typically tried to stay towards one side of the range with the new shims. Can't remember if it was the upper or lower end of the range.
Thanks,
Rookie2
When you replaced the shims, was there a particular side of the range you leaned toward for the new shims? Seems like I recall there being some discussion about this (Robbie IIRC), and I think he typically tried to stay towards one side of the range with the new shims. Can't remember if it was the upper or lower end of the range.
Thanks,
Rookie2
I shot for the middle as I didn't have the confidence to go tighter. All mine were on the loose side. I was able to move some of them around to help save on needed shims. Initially I needed 21 shims but some of the ones that were out went into other places to help reduce the number needed.
BTW, my startup rattle disappeared the day I finished with the shims. This is one of those jobs that everyone puts off. If you have over 120k I'd order a valve cover gasket and at least measure them to see where you're at.
BTW, my startup rattle disappeared the day I finished with the shims. This is one of those jobs that everyone puts off. If you have over 120k I'd order a valve cover gasket and at least measure them to see where you're at.
semlin
curmudgeon
interesting. I had a valve grind recently as part of a h/g saga and they told me they set the tolerances on the valves to factory spec. i assume they didn't replace any pucks since i wasn't charged for any. how did they adjust it?
They're not adjustable valves. They can only be adjusted by changing the shims.
If they ground the valves they should have all been too tight and all needing replacement. I'd say they didn't grind the valves as the alternative of re-using the old shims would be disastrous.
powderpig
SILVER Star
the adjustment at the machine shop is to shave off a little of the valve stem to get the correct distance. I would shoot for the middle of the spread if you can.
Rick, did you find that all was exactly as you planned when you replaced the shims? Meaning that all worked well when you put in the shims. Or did a few create a reading of the shim thickness. my experence is that usually one or two will create a bit of a problem and I usually have to sacrifice one being a little higher or lower, but still with in the specs. A micrometer is a must for this as a caliper can miss read the shims more easly(just my personal biasis).
any how, good luck and you must get a FSM as well to do this, it is the only way to order the shims, unless you happen to have the microfisch or a parts manual. Later robbie
Rick, did you find that all was exactly as you planned when you replaced the shims? Meaning that all worked well when you put in the shims. Or did a few create a reading of the shim thickness. my experence is that usually one or two will create a bit of a problem and I usually have to sacrifice one being a little higher or lower, but still with in the specs. A micrometer is a must for this as a caliper can miss read the shims more easly(just my personal biasis).
any how, good luck and you must get a FSM as well to do this, it is the only way to order the shims, unless you happen to have the microfisch or a parts manual. Later robbie
Robbie, they all seemed to work out to within the specs but not necessarily the math. I attribute this to the oil in the system. If I were to do it again I'd probable pull the cams and clean of the oil then reassemble to get a better feel.
A friend of mine grinds his shims on his racing bikes to get perfect clearances. This however requires that the shim get hardened again. I would think this would apply to the valve stem also, or wouldn't it?
A friend of mine grinds his shims on his racing bikes to get perfect clearances. This however requires that the shim get hardened again. I would think this would apply to the valve stem also, or wouldn't it?
The factory-recommended interval is 60,000 miles.
I checked mine at ~92,000 miles and they were all in the middle of the range.
Incorrect answer:
Correct answer:
When a valve and seat are ground, the valve stem "moves up" in the guide. If this is not addressed the valve will be too long. The machinist "nips" the top of the valve stem to true it and to restore the geometry.
Grench
SILVER Star
Since this procedure puts us at the cam shaft...
Are there more aggressive cams that can be swaped in during this? Is there a performance gain to be had? At the expense of...???
Are there more aggressive cams that can be swaped in during this? Is there a performance gain to be had? At the expense of...???
semlin
curmudgeon
ok, now that i think about it, i remember the machinist coming into the shop as i was settling up to ask the mileage and telling me it was impressive that everything was in perfect spec given the mileage so putting two and two together the valves were still in spec at 155k.
would they really use valve stem nip instead of replacing pucks? i can see the amount of the nip matching the amount of the grind being a one time measurement but wouldn't it be pretty darn fiddly to reassemble after one valve nip to adjust for the grind, measure all the discrepencies, pull those valves out of alignment and nip the stems again? or could they maybe measure before disassembly and take it into account when they nip?
i'm thinking i should have asked more questions at the valve grind to see how they did it. it seems like it would be possible for a machine shop to shortcut this process.
semlin
curmudgeon
i don't know the answer but i wouldn't call that a "while you are there" repair. It is not that difficult/time consuming to get the valve cover off and replace the cams. I would say that's a mod that would stand or fail on its own merits rather than something to consider simply because you are already going to the effort of adjusting the valves.
