WHAT`S THE BEST WAY TO ADJUST THE VALVES, WHEN ENGINE IS RUNNING SO YOU DONT SPILL OIL? I DONT HAVE AN OLD SET OF VALVE COVERS THAT I CAN CUT OPEN TO ADJUST.
Original Post
Replies sorted oldest to newest
Rocker Stoppers:
quote:Originally posted by webbers:
WHAT`S THE BEST WAY TO ADJUST THE VALVES, WHEN ENGINE IS RUNNING SO YOU DONT SPILL OIL? I DONT HAVE AN OLD SET OF VALVE COVERS THAT I CAN CUT OPEN TO ADJUST.
With the engine off. That is the way the shop manual instructs. It's amazing how few people read this stuff.
> With the engine off. That is the way the shop manual instructs.
> It's amazing how few people read this stuff.
If you have a cam with any sort of overlap, you do not want to
follow the shop manual method of setting the valves. Instead,
you need to follow the firing order. With a warmed up engine,
turn the motor over by hand, set the intake lash just as the
exhaust valve begins to open. Set the exhaust lash just before
the intake valve closes. Proceed to the next valve in the firing
order and repeat.
Dan Jones
> It's amazing how few people read this stuff.
If you have a cam with any sort of overlap, you do not want to
follow the shop manual method of setting the valves. Instead,
you need to follow the firing order. With a warmed up engine,
turn the motor over by hand, set the intake lash just as the
exhaust valve begins to open. Set the exhaust lash just before
the intake valve closes. Proceed to the next valve in the firing
order and repeat.
Dan Jones
Dan -
Just curious. Why do you need to follow the firing order? I've followed Tom Monroe's instructions which allow you to set all the valves with just three engine positions instead of 16. Is there much difference between the two methods?
Just curious. Why do you need to follow the firing order? I've followed Tom Monroe's instructions which allow you to set all the valves with just three engine positions instead of 16. Is there much difference between the two methods?
> Just curious. Why do you need to follow the firing order? I've followed Tom
> Monroe's instructions which allow you to set all the valves with just three
> engine positions instead of 16. Is there much difference between the two
> methods?
The method I suggested is the SAE method and works for all cams.
The method Tom Monroe shows is the same as the factory manual and
only works with cams of little or no overlap. If your cam has a
decent amount of overlap, all the valves must be set individually
when the lifter is located on the base circle of the lobe. At
that position, the valve is closed and there is no lift taking
place. If you have zero overlap, the factory manual approach
will also do that. However, addd in overlap, and that won't
necessarily be the case. It's always best to watch the valve
motion and chase the firing order. IIRC, you had some problems
with setting the lash on your Comp 282S. Using Monroe's method
may have contributed to that.
Dan Jones
> Monroe's instructions which allow you to set all the valves with just three
> engine positions instead of 16. Is there much difference between the two
> methods?
The method I suggested is the SAE method and works for all cams.
The method Tom Monroe shows is the same as the factory manual and
only works with cams of little or no overlap. If your cam has a
decent amount of overlap, all the valves must be set individually
when the lifter is located on the base circle of the lobe. At
that position, the valve is closed and there is no lift taking
place. If you have zero overlap, the factory manual approach
will also do that. However, addd in overlap, and that won't
necessarily be the case. It's always best to watch the valve
motion and chase the firing order. IIRC, you had some problems
with setting the lash on your Comp 282S. Using Monroe's method
may have contributed to that.
Dan Jones
Yes, that is the reason to vary from the Shop Manual settings.
But, let me say that my experience in adjusting the 289 series (302,351w) and 351c series (yep Boss 302, too) with both solid lifters and hydraulic lifters with hot street cams up to around 246 @ .050, the shop manual is fine and accurate.
If it works for roller lifters, I don't know.
If you are in doubt use Dan's method to be safe.
If you are using hydraulic lifters or even a stock factory performance hydraulic cam, I just don't see where it is going to matter at all.
I wouldn't bother with the longer method in my shop and I would guaranty the work, but that's just me.
But, let me say that my experience in adjusting the 289 series (302,351w) and 351c series (yep Boss 302, too) with both solid lifters and hydraulic lifters with hot street cams up to around 246 @ .050, the shop manual is fine and accurate.
If it works for roller lifters, I don't know.
If you are in doubt use Dan's method to be safe.
If you are using hydraulic lifters or even a stock factory performance hydraulic cam, I just don't see where it is going to matter at all.
I wouldn't bother with the longer method in my shop and I would guaranty the work, but that's just me.
quote:
The method I suggested is the SAE method and works for all cams.
The method Tom Monroe shows is the same as the factory manual and
only works with cams of little or no overlap. If your cam has a
decent amount of overlap, all the valves must be set individually
when the lifter is located on the base circle of the lobe. At
that position, the valve is closed and there is no lift taking
place. If you have zero overlap, the factory manual approach
will also do that. However, addd in overlap, and that won't
necessarily be the case. It's always best to watch the valve
motion and chase the firing order. IIRC, you had some problems
with setting the lash on your Comp 282S. Using Monroe's method
may have contributed to that.
Dan Jones
Thanks for the clarification - makes sense. And as further clarification, yes I had all kinds of problems with my CompCams 282S, but none of them were related to how I set lash (I think). The list of problemas was long... Setting lash via the shop manual method wouldn't have HELPED the situation any, that's for sure.
Charlie I had problems with the last engine I built with a very similar profile to the 282s in a 347 and a Compcam.
It illustrated to me the signifigance of the abcense of the zinc addative in the engine oil.
I don't know if you remember that thread that we had here on this Forum?
It illustrated to me the signifigance of the abcense of the zinc addative in the engine oil.
I don't know if you remember that thread that we had here on this Forum?
> Yes, that is the reason to vary from the Shop Manual settings.
> But, let me say that my experience in adjusting the 289 series (302,351w)
> and 351c series (yep Boss 302, too) with both solid lifters and hydraulic
> lifters with hot street cams up to around 246 @ .050, the shop manual is
> fine and accurate.
Remember that overlap is a function of both duration and lobe separation
angle, with the latter providing more overlap for each degree. Those
factory grind cams had wide lobe separations, on the order of 114 to 116
degrees in many cases. A cam with 106 lobe separation is a completely
different case.
Dan Jones
> But, let me say that my experience in adjusting the 289 series (302,351w)
> and 351c series (yep Boss 302, too) with both solid lifters and hydraulic
> lifters with hot street cams up to around 246 @ .050, the shop manual is
> fine and accurate.
Remember that overlap is a function of both duration and lobe separation
angle, with the latter providing more overlap for each degree. Those
factory grind cams had wide lobe separations, on the order of 114 to 116
degrees in many cases. A cam with 106 lobe separation is a completely
different case.
Dan Jones