Timing issue

Message

quadsourcemark · #81 Post by **quadsourcemark** » Fri Mar 06, 2009 3:08 am

QUOTE (cannondale27 @ Mar 6 2009, 01:08 AM) <{POST_SNAPBACK}>

Okay this is going to come off bad but its really obvious you have no clue what is going on.I tried to help and you wont even answer some simple questions such as valve clearance and decomp clearance.Please get someone to look at your motor or send it out.Otherwise you are just wasting all our time and your $.Sorry for being blunt but you will thank me later.

You said: I would bet you got a redone cam which base circle was cut down.

A I said several times I replaced the INTAKE CAM not the exhaust cam. The exhaust cam is the same cam I've been running since I've owned it. It started normal and had normal compression until the decomp weight broke.

EXHAUST CLEARENCE: .014 (BOTH)
DECOMP PIN CLEARENCE: .028 PLUS

The reason it's noted plus is because when I measure the pin has up/down movement. As I said earlier I should have replaced the entire decomp assy. Sorry for wasting your time.

peterock · #82 Post by **peterock** » Fri Mar 06, 2009 3:23 am

something tells me you are going to have the same problem even with a new decomp pin. While cranking, a loose or hung up pin isn't going to lower your compression. At worst, if your decomp isn't working correctly you will have to high of compression and will have a hard time turning the motor over. Your best bet is going to be to do as mentioned. Post a pic of how you have it set-up. Lets see where your cam lobes are in relation to top dead center and tooth alignment.

quadsourcemark · #83 Post by **quadsourcemark** » Fri Mar 06, 2009 6:36 am

QUOTE (peterock @ Mar 6 2009, 03:23 AM) <{POST_SNAPBACK}>

something tells me you are going to have the same problem even with a new decomp pin. While cranking, a loose or hung up pin isn't going to lower your compression. At worst, if your decomp isn't working correctly you will have to high of compression and will have a hard time turning the motor over. Your best bet is going to be to do as mentioned. Post a pic of how you have it set-up. Lets see where your cam lobes are in relation to top dead center and tooth alignment.

Well the exhaust cam is apart. I can put the gear back on and put the cam back in place for photos. I'll post them ASAP.

Mark

cannondale27 · #84 Post by **cannondale27** » Fri Mar 06, 2009 12:37 pm

QUOTE (quadsourcemark @ Mar 5 2009, 09:08 PM) <{POST_SNAPBACK}>

You said: I would bet you got a redone cam which base circle was cut down.

A I said several times I replaced the INTAKE CAM not the exhaust cam. The exhaust cam is the same cam I've been running since I've owned it. It started normal and had normal compression until the decomp weight broke.

EXHAUST CLEARENCE: .014 (BOTH)
DECOMP PIN CLEARENCE: .028 PLUS

The reason it's noted plus is because when I measure the pin has up/down movement. As I said earlier I should have replaced the entire decomp assy. Sorry for wasting your time.

Thank You for eliminating that possibility.Have you removed the bucket from the exhaust valve decomp opens?Take a look and see if the valve and keepers are sunk into the retainer or retainer itself cracked.If bucket acts upon the retainer rather than shim it can also do this.

quadsourcemark · #85 Post by **quadsourcemark** » Fri Mar 06, 2009 4:42 pm

QUOTE (cannondale27 @ Mar 6 2009, 12:37 PM) <{POST_SNAPBACK}>

Thank You for eliminating that possibility.Have you removed the bucket from the exhaust valve decomp opens?Take a look and see if the valve and keepers are sunk into the retainer or retainer itself cracked.If bucket acts upon the retainer rather than shim it can also do this.

Yes I inspected the valve buckets several times. I also shimmed and re- shimmed all including removing all the valve keepers, base, spring etc. I'll recheck the valve assy were the decomp pin strikes. Here's pics of my timming marks. Sorry for the quality.

Mark

Canniboomer · #86 Post by **Canniboomer** » Fri Mar 06, 2009 7:06 pm

Check your Oilpump Idler Gear, and the Scavenge Gear next to that (not pictured).
That E-clip looks too small for the shaft and ready to spit off. And note the groove width is narrower on the idler shaft.
Any type of clip should be 1mm max thickness there. For stock hardware, they used a circlip there.
If you are using stock parts, then you have switched the circlip and the E-clip.

cannondale27 · #87 Post by **cannondale27** » Fri Mar 06, 2009 9:07 pm

Good catch.

Timing is right as far as I can tell.Now I am feeling your frustration.Maybe like you said decomp is so bagged out its somehow getting cocked and opening valve to far.Just never seen something like that.Hope you take some pics of decomp mechanism so we can all see what to look for.

quadsourcemark · #88 Post by **quadsourcemark** » Sat Mar 07, 2009 1:19 am

QUOTE (cannondale27 @ Mar 6 2009, 09:07 PM) <{POST_SNAPBACK}>

Good catch.

Timing is right as far as I can tell.Now I am feeling your frustration.Maybe like you said decomp is so bagged out its somehow getting cocked and opening valve to far.Just never seen something like that.Hope you take some pics of decomp mechanism so we can all see what to look for.

I do have the other clip so I'll make that swap. I'll let you guys know if the new decomp corrects my issues. I did notice the grove in the cam that saddles the pin has some wear. I'm considering replacing the exhaust cam. I'll assemble it and see how it goes. I'll try to post some pics in a day or two regarding the results. Has anyone replaced the decomp weight using the allen head screw and backing nut?

Thanks again,
Mark

rayspeed · #89 Post by **rayspeed** » Sat Mar 07, 2009 2:57 am

It might just be me or the pictures but the nearest lobe on the intake cam looks a little flat. Did you measure it?

quadsourcemark · #90 Post by **quadsourcemark** » Sat Mar 07, 2009 4:12 pm

QUOTE (rayspeed @ Mar 7 2009, 02:57 AM) <{POST_SNAPBACK}>

It might just be me or the pictures but the nearest lobe on the intake cam looks a little flat. Did you measure it?

Yes I measured them all. I used my Blackberry for the photos. My camera is MIA!

Thanks,
Mark