Do you have to degree a new cam ?

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Author Topic: Do you have to degree a new cam ?  (Read 482785 times)

Offline Fitzy1980

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Re: Do you have to degree a new cam ?
« Reply #850 on: March 28, 2016, 07:55:07 pm »
:lmao:

HEY, DID IT HAVE A MILD OR KIND OF NASTY IDLE BEFORE WHEN YOU FIRST GOT IT?

WHAT IS YOUR ROCKER RATIO?
.

It was pretty choppy, definitely noticed it.

Why's that ?

Will the new cam be lopey ?

1.70

Offline barnett468

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Re: Do you have to degree a new cam ?
« Reply #851 on: March 29, 2016, 04:09:03 am »
It was pretty choppy, definitely noticed it.

Why's that ?

Will the new cam be lopey ?

1.70

just curious.

if anything the new cam may be a little lopier.

.

Offline barnett468

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Re: Do you have to degree a new cam ?
« Reply #852 on: March 29, 2016, 05:08:36 am »
ok, the cam mfg's don't know the base circle size but that's ok.

Did you rotate/unthread the nuts on the screws at all or did you just loosen the nut then turn the screws out? 

How far are the rocker shafts from being bolted to the head, 2 mm 4 mm etc?

From the looks of it so far I think you should buy a cheap 6.80" and 6.75" long push rod and try both of those.


1. Remove rocker set from number 1 cylinder and clean the top of the valve stem with cleaner.

2. Color the top of the valve stem with felt pen or dykem.

3. Install one push rod on the intake valve and the other one on the exhaust valve then tighten rocker shaft bolts.

4. Adjust to .021" and tighten nuts then take photo of adjusting screws.

5. Rotate engine clockwise 4 full turns.

6. Remove rocker set and measure the width of the pattern on both valve tips.

7. Take a close up photo in which we can see both valve tips at the same time.

If the pattern is definitely narrower on one tip, you want that push rod length that was on that rocker.

If the pattern is similar, you want the push rod that makes the pattern closest to the center of the valve.

This will get you plenty close enough for your app.

 













« Last Edit: March 29, 2016, 06:58:46 am by barnett468 »

Offline Fitzy1980

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Re: Do you have to degree a new cam ?
« Reply #853 on: March 29, 2016, 09:28:07 am »
I'll get on to it this morning.

I rotated the locking nut all the way out then unthreaded the screws out till they stopped.

Only thing is you said .21, if i tighten the shaft bolts i can't get a feeler gauge in there at all. I wouldn't even get .010 in there.

As soon as i torque them down to the recommended torque which is 40 ft lbs it's all tight. It's tight if i just finger tighten them,

They probably have a coupe of mm

But ill do what you have said

I'll do a few things and post photos so it's clearer in what im saying


Other thing, if i'm rotating the engine all the time am i wiping the cam lube off ?
« Last Edit: March 29, 2016, 09:49:49 am by Fitzy1980 »

Offline barnett468

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Re: Do you have to degree a new cam ?
« Reply #854 on: March 29, 2016, 09:58:08 am »
Read my post again .  I said install the new push rods first, then tighten the rockers then adjust the lash.

Don't worry about the lube, Cait says she has used it before and it took her days to rub it completely off.

Your push rods have ZERO freeplay.

The bottom side of your shaft is around 2 mm above the mounting pad on the head.

If you tighten the mounting bolts, it will open the valves slightly

I knew this days ago but now I have the measurement I need.

One of the push rod lengths I suggested should work . See how easy and painless that was.
.

« Last Edit: March 29, 2016, 10:02:48 am by barnett468 »

Offline barnett468

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Re: Do you have to degree a new cam ?
« Reply #855 on: March 29, 2016, 10:03:56 am »

Ok. so am still doing everything you asked ?

what do you mean?

buy the two different length push rods and do the test i suggested.

Offline Fitzy1980

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Re: Do you have to degree a new cam ?
« Reply #856 on: March 29, 2016, 10:06:15 am »
what do you mean?

buy the two different length push rods and do the test i suggested.

I misread your post earlier.

I'll suss the rods now

Offline barnett468

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Re: Do you have to degree a new cam ?
« Reply #857 on: March 29, 2016, 10:08:49 am »
I misread your post earlier.

I'll suss the rods now

Are they close enough to get today and install them?

Get a third rod that is .225 shorter . If they don't have that then get .250" shorter.
« Last Edit: March 29, 2016, 10:18:51 am by barnett468 »

Offline barnett468

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Re: Do you have to degree a new cam ?
« Reply #858 on: March 29, 2016, 10:17:21 am »
Just for fun.

.080" [2 mm] x 1.7 = .136

if you get rods that are .136" shorter and tighten the rockers, you will have around ZERO freeplay.

You need .022 freeplay so .136 + .022 = .158 . but this will still leave your rocker adjusting screws bottomed out in the fully loose position so you need to have then screwed in a little so a rod that is .200 shorter will move the screws .042" from the bottomed position.

Get a third rod that is .225 shorter . If they don't have that then get .250" shorter.
.
« Last Edit: March 29, 2016, 10:19:45 am by barnett468 »

Offline Fitzy1980

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Re: Do you have to degree a new cam ?
« Reply #859 on: March 29, 2016, 10:17:52 am »
Are they close enough to get today and install them?

No mate, everything is either Sydney ( 4 hr+ round trip ) or another state.

Pita  :thud:

I'll call them shortly, i can get them over night to me

Offline Fitzy1980

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Re: Do you have to degree a new cam ?
« Reply #860 on: March 29, 2016, 10:19:39 am »
Just for fun.

.080" [2 mm] x 1.7 = .136

if you get rods that are .136" shorter and tighten the rockers, you will have around ZERO freeplay.

You need .022 freeplay so .136 + .022 = .158 . but this will still leave your rocker adjusting screws bottomed out in the fully loose position so you need to have then screwed in a little so a rod that is .200 shorter will move the screws .042" from the bottomed position.


Get a third rod that is .225 or .250 shorter.

.

Sorry Barn i don't speak Klingon...  :shrug:

 :lmao:

Offline barnett468

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Re: Do you have to degree a new cam ?
« Reply #861 on: March 29, 2016, 10:25:53 am »
Sorry Barn i don't speak Klingon...  :shrug:

 :lmao:

How much did they pay you at that mining job?

Buy a 6.800" long, 6.750" long, and 6.700" long push rod in the cheapest brand you can.

One of these lengths will be good.
.
« Last Edit: March 29, 2016, 10:29:37 am by barnett468 »

Offline boofhead

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Re: Do you have to degree a new cam ?
« Reply #862 on: March 29, 2016, 10:38:06 am »
An adjustable one to test/determine the length can help as well.

Offline barnett468

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Re: Do you have to degree a new cam ?
« Reply #863 on: March 29, 2016, 10:53:19 am »
An adjustable one to test/determine the length can help as well.

boofead, Shaunp said an adjustable one will bend and Fitzy is unable to change valve springs.


Offline Fitzy1980

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Re: Do you have to degree a new cam ?
« Reply #864 on: March 29, 2016, 11:59:59 am »
boofead, Shaunp said an adjustable one will bend and Fitzy is unable to change valve springs.

I could but thats another 40 pages..

 :lmao: :lmao: :lmao: :lmao:

Offline Fitzy1980

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Re: Do you have to degree a new cam ?
« Reply #865 on: March 29, 2016, 12:03:11 pm »
How much did they pay you at that mining job?

Well..

 :lmao:

Buy a 6.800" long, 6.750" long, and 6.700" long push rod in the cheapest brand you can.

One of these lengths will be good.

Roger that.

I think comp have ones for a few bucks



Do i need to worry about wall thick ness etc for these test ones

Also it looks like Trend rods go up in 0.25 increments, would these be better over the 0.50 ?
« Last Edit: March 29, 2016, 12:09:01 pm by Fitzy1980 »

Offline barnett468

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Re: Do you have to degree a new cam ?
« Reply #866 on: March 29, 2016, 12:20:49 pm »
Do i need to worry about wall thickness etc for these test ones

Also it looks like Trend rods go up in 0.25 increments, would these be better over the 0.50 ?

No need to worry about wall thickness for this test . Buy the cheapest pos rods you can.

My rod length suggestions are based on your 2 mm estimate of rocker pivot to mounting pad clearance and looking at you rocker adjusting screws, so that is my best guess from what I can see sitting behind a computer 6.000 miles away.

Don't start getting anal on me now .  :lmao:
.
« Last Edit: March 29, 2016, 12:23:28 pm by barnett468 »

Offline Fitzy1980

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Re: Do you have to degree a new cam ?
« Reply #867 on: March 29, 2016, 12:26:12 pm »
No need to worry about wall thickness for this test . Buy the cheapest pos rods you can.

My rod length suggestions are based on your 2 mm estimate of rocker pivot to mounting pad clearance and looking at you rocker adjusting screws, so that is my best guess from what I can see sitting behind a computer 6.000 miles away.

Don't start getting anal on me now .  :lmao:
.

I'll get some photos now

I'm not sure if this is any help

The 3 nuts on the shaft are only lightly finger tightened, there is zero movement on the rocker so much so i can't fit a 0.002 gauge in there. I can spin the rods easily but if i torque the shaft down there is no play at all on the rod. The adjustment screws are also wound right out till i can't turn them any further. Would take a lot of force.


2016-03-29_12-35-53 by , on Flickr
« Last Edit: March 29, 2016, 12:46:06 pm by Fitzy1980 »

Offline Fitzy1980

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Re: Do you have to degree a new cam ?
« Reply #868 on: March 29, 2016, 01:04:20 pm »
Right, bit of ringing around i have the rods coming over night.

Anyway, in the meantime ill put the intake and crap on.

I take it leave the fuel pump out till the valves are sorted ?
« Last Edit: March 29, 2016, 01:13:18 pm by Fitzy1980 »

Offline barnett468

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Re: Do you have to degree a new cam ?
« Reply #869 on: March 29, 2016, 01:11:55 pm »

That is far less than 2 mm of clearance between the head and the shaft.

Tighten the nuts on the shaft finger tight.

tighten the nuts on the shaft with a ratchet until they are properly tight and count how many turns it takes to tighten them.

« Last Edit: March 29, 2016, 01:15:06 pm by barnett468 »

Offline Fitzy1980

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Re: Do you have to degree a new cam ?
« Reply #870 on: March 29, 2016, 01:14:02 pm »
That is far less than 2 mm of clearance between the head and the shaft.

Yeah, i just realised that.

Can the rods before they send them ?

Offline barnett468

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Re: Do you have to degree a new cam ?
« Reply #871 on: March 29, 2016, 01:16:03 pm »
Yeah, i just realised that.

Can the rods before they send them ?

You still need new rods but i will give you new lengths.  :toetapping:

Tighten the nuts on the shaft finger tight.

tighten the nuts on the shaft with a ratchet until they are properly tight and count how many turns it takes to tighten them.

Offline Fitzy1980

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Re: Do you have to degree a new cam ?
« Reply #872 on: March 29, 2016, 01:18:17 pm »
That is far less than 2 mm of clearance between the head and the shaft.

Tighten the nuts on the shaft finger tight.

tighten the nuts on the shaft with a ratchet until they are properly tight and count how many turns it takes to tighten them.


Does 40 ft lbs sound right, its what i found on T&D's specs online

http://www.tdmach.com/05850.pdf

I'll ring them to hold sending them

Offline barnett468

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Re: Do you have to degree a new cam ?
« Reply #873 on: March 29, 2016, 01:22:40 pm »
Does 40 ft lbs sound right, its what i found on T&D's specs online

http://www.tdmach.com/05850.pdf

I'll ring them to hold sending them

you dont need 40 now just use 20.

i can give you the new rod info right away.


Offline Fitzy1980

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Re: Do you have to degree a new cam ?
« Reply #874 on: March 29, 2016, 01:33:30 pm »
you dont need 40 now just use 20.

i can give you the new rod info right away.

About 3/4 turn at 40

Bit over 1/4 turn at 20