Camshafts in sync?

Tor-King · December 27, 2018, 01:03:29 PM

Hi guys!
I know I have not been on for awhile... but I do visit everyday!! I am now finishing up rebuilding my engine and have a question about camshaft timing... I have the crank at TDC #1, camshaft lobes are facing out on #1, the marks on both cam gears are flush with the head surface, the dimples on both cams are visible in #3 cam bearings and chain is taut. But yet, the T on the pickup coil timing plate is ever so slightly passed the mark on the pickup coil. See pictures. Is this thing in time? I believe if I adjust it back one tooth, it will be way further out of time... Your expertise is required.
Thanks,
Dean

racerrad8 · December 27, 2018, 06:57:59 PM

It is probably off one tooth on the crank.

Rotate the crank around and one up the timing Mark on the rotor. The cams will then out of time.

Randy - RPM

Tor-King · December 27, 2018, 08:07:59 PM

Quote from: racerrad8 on December 27, 2018, 06:57:59 PM
It is probably off one tooth on the crank.

Rotate the crank around and one up the timing Mark on the rotor. The cams will then out of time.

Randy - RPM

Hi Randy.
I THINK I have it figured out. The T is now lined up with the pickup coil and both (intake and exhaust) dimpled marks are showing in the #3 cam bearings. The exhaust cam dimple mark is centred in the #3 cap sight hole while the intake dimple mark is slightly forward (but still clearly showing) in the sight hole. Is all good?
THANKS!
Dean

racerrad8 · December 27, 2018, 10:05:41 PM

Not sure without seeing it. Make sure you are only rotating the crank counter clockwise to kine up the timing mark.

The final check is the holes drilled in the end Cam lobe. When it is timed properly, the hole is perfectly split on the head surface.

Randy - RPM

Tor-King · December 27, 2018, 11:13:24 PM

Quote from: racerrad8 on December 27, 2018, 10:05:41 PM
Not sure without seeing it. Make sure you are only rotating the crank counter clockwise to kine up the timing mark.

The final check is the holes drilled in the end Cam lobe. When it is timed properly, the hole is perfectly split on the head surface.

Randy - RPM

Just when I thought I had it - NOT. The final check you proposed, failed. If I move the crank so the exhaust cam lobe hole is perfectly split, the intake is too high!! UGH! If I am out one tooth on the crank, which I now believe I am, how do I move it? Not having fun.

Troyskie · December 27, 2018, 11:42:44 PM

Mate, remove the pick-up coil plate and see if a PO has done a timing advance.

If it is then you'll see that the mounting screw holes for the pick-up plate are elongated if it has been advanced.

RPM - Robert · December 28, 2018, 10:04:08 AM

Quote from: Troyskie on December 27, 2018, 11:42:44 PM
Mate, remove the pick-up coil plate and see if a PO has done a timing advance.

If it is then you'll see that the mounting screw holes for the pick-up plate are elongated if it has been advanced.

It doesn't appear to have timing added at the plate, the pickup would be closer towards the 12 o/clock position (not that far up but in that direction). The pickup is lined up with the crank case halves; which means it has no timing at the plate.

Tor, you will need to remove the cams and start over (at least one cam, you might be able to slack it enough with the other in that you can get it down a tooth at the crank). These are what we suggest for most people building their own FJ engines. Slotted Camshaft Gears If you don't do a lot of them or a lot of engine work getting the timing right can be a real PITA sometimes. These make getting the timing perfect a breeze. If you are a tooth off somewhere they are easily adjusted to get the timing spot on.

Troyskie · December 28, 2018, 08:13:52 PM

Cool mate.

I remember having to put the cams in a couple of times before I rang Pete and asked if he could help.

Tor-King · December 29, 2018, 02:58:38 PM

Alright, after about the 10th time, this is what I got...

If it is not correct, it looks like slotted cam gears are in my future! BTW, being slotted, is there a chance that the gears may "slip" once installed?
Dean

racerrad8 · December 29, 2018, 03:55:07 PM

Quote from: Tor-King on December 29, 2018, 02:58:38 PM
Alright, after about the 10th time, this is what I got... If it is not correct, it looks like slotted cam gears are in my future! BTW, being slotted, is there a chance that the gears may "slip" once installed?
Dean

Looks pretty close. It is hard to tell if the crank is properly lined up. It looks like its 10* past the crankcase parting line.

It need to be lined up perfectly. That is tdc, if the timing chain is stretched, then to get the cams properly timed, slotted gears compensates for the stretched chain.

Randy - RPM

Tor-King · December 30, 2018, 09:17:40 PM

Hey Randy.
I pm'd you.

Thanks,
Dean

ribbert · December 31, 2018, 07:12:55 AM

Quote from: Tor-King on December 29, 2018, 02:58:38 PM

.......... it looks like slotted cam gears are in my future! BTW, being slotted, is there a chance that the gears may "slip" once installed?

Dean

Randy has referred in the past to them slipping but I've had no problem with mine.

Noel

Tor-King · December 31, 2018, 12:32:18 PM

Alright Randy,
Here are some recent pictures taken. Cam chain is tight with tensioner installed, engine turned over a number of times. What is your take? Fingers crossed...
Dean

racerrad8 · December 31, 2018, 01:14:52 PM

I think you are good to go.

The slotted cam gears will allow you to get them perfectly centered. With the chain stretch you have, you are right there.

Randy - RPM

JMR · January 04, 2019, 05:58:48 AM

I've timed hundreds of cams and never had a slotted sprocket slip. Clean everything well with brake cleaner and use blue Loctite or Three Bond Medium High Temp threadlock.
The FJ sprocket bolts are nice compared to others....I use them on SOHC Honda's all the time.

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Camshafts in sync?