Timing issue

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cannondale27 · #51 Post by **cannondale27** » Mon Mar 02, 2009 12:24 pm

Or if a valve just isnt sealing.

quadsourcemark · #52 Post by **quadsourcemark** » Mon Mar 02, 2009 5:16 pm

QUOTE (cannondale27 @ Mar 2 2009, 12:24 PM) <{POST_SNAPBACK}>

Or if a valve just isnt sealing.

The valves are sealing. I verified this again. I also verified the timming again. The decomp lever should be on until it starts? It should have around 80lbs with the decomp lever on? How much total compression with the decomp off?

Thanks,
Mark

peterock · #53 Post by **peterock** » Mon Mar 02, 2009 6:18 pm

Decomp pin shouldn't be your issue if using stock cams.

Please verify what your compression is when fully assembled correctly, cranking over, with throttle wide open.

quadsourcemark · #54 Post by **quadsourcemark** » Mon Mar 02, 2009 7:10 pm

QUOTE (peterock @ Mar 2 2009, 06:18 PM) <{POST_SNAPBACK}>

Decomp pin shouldn't be your issue if using stock cams.

Please verify what your compression is when fully assembled correctly, cranking over, with throttle wide open.

I'll check when I get home from work. I'm running stock cams. Well I did replace the intake cam with a cam from Brad @ black widow. It only has one set of cam pin holes. The gear still has multiple holes. Not sure if it's stock or something Brad had made. I don't think that should be an issue. I'll post my compression results tonight.

Thanks,
Mark

peterock · #55 Post by **peterock** » Mon Mar 02, 2009 7:23 pm

That is a stock cam.

quadsourcemark · #56 Post by **quadsourcemark** » Mon Mar 02, 2009 7:44 pm

QUOTE (peterock @ Mar 2 2009, 07:23 PM) <{POST_SNAPBACK}>

That is a stock cam.

Ok. The intake cam I pulled had multiple holes like the cam gear. It also had the part number scribed between the lobes.

Mark

quadsourcemark · #57 Post by **quadsourcemark** » Mon Mar 02, 2009 11:56 pm

QUOTE (quadsourcemark @ Mar 2 2009, 07:44 PM) <{POST_SNAPBACK}>

Ok. The intake cam I pulled had multiple holes like the cam gear. It also had the part number scribed between the lobes.

Mark

Ok I have 190 lbs of compression with then decomp lever dis-engaged.....20 lbs with it engaged. I used my car with jumper cables when I checked it. When it got to 190 the starter struggled to turn it over. I believe it should have a round 80 lbs with the decomp engaged. The ring end gap is well in spec. Intake and exhaust valves are shimmed and I pressurized the head and have no leakage.

Mark

thedeatons · #58 Post by **thedeatons** » Tue Mar 03, 2009 1:27 am

I would consider 80 a bit low personally. I think the lowest I have seen on my rebuilds was 87, usually 90-100.

Did you verify all you cam timing dots line up when at TDC?

2mike18 · #59 Post by **2mike18** » Tue Mar 03, 2009 2:29 am

I dont have a lot of experiance with dales compared to the others but I have a few things to offer that may help you. engines need three things to run 1 air 2 fuel and 3 spark with that said the recommended compression for a rebuild is 90psi so I would imagine that with the decomp ON the pressure would need to be in that area like 80ish or higher to start up. If your only getting 30psi with the decomp on it wont start I've had a motor that at 60psi would not start up. engines are like an air pump in the fact that they pull air in they compress the air and the they expell the air only difference between that and a four stroke motor is after compression there is the detonation stroke. I'm not trying to offend you or your intelligence just throwing two things to consider as a process to find your problem. my thought is on your compression stroke during start up since you say 30psi. why so low??? good luck on your project

P.S. take a few pics of things and post them a lot of these guys may see something easily overlooked that has not been realized yet.

quadsourcemark · #60 Post by **quadsourcemark** » Tue Mar 03, 2009 3:39 am

QUOTE (darkknight @ Mar 3 2009, 02:29 AM) <{POST_SNAPBACK}>

I dont have a lot of experiance with dales compared to the others but I have a few things to offer that may help you. engines need three things to run 1 air 2 fuel and 3 spark with that said the recommended compression for a rebuild is 90psi so I would imagine that with the decomp ON the pressure would need to be in that area like 80ish or higher to start up. If your only getting 30psi with the decomp on it wont start I've had a motor that at 60psi would not start up. engines are like an air pump in the fact that they pull air in they compress the air and the they expell the air only difference between that and a four stroke motor is after compression there is the detonation stroke. I'm not trying to offend you or your intelligence just throwing two things to consider as a process to find your problem. my thought is on your compression stroke during start up since you say 30psi. why so low??? good luck on your project

P.S. take a few pics of things and post them a lot of these guys may see something easily overlooked that has not been realized yet.

Darknight.......I'm not offended in anyway. That????????s why there's forums. Well I tried one more thing. I removed the return spring from the counter weight and got exactly 90 lbs of compression. I also dis-engaged the decomp and got around 190 lbs. I stopped at 190 lbs because it struggles to turn over. I need to verify the spring is connected correctly and is not damaged, shortened, stretched, etc.

Thanks,
Mark