420A 420a Timing belt loose

[Danny3288]

Hello all. I've had 15 Eclipses, both 420as and 4g63s. I've done many timing belts.

My question is this, I had my cylinder head worked on (machined and new valves), new water pump, new bearings, new timing belt and new tensioner. I've timing it like I've always done, the correct way. The problem that I'm having is not the marks lining up, but a lot of slack in the belt between the cam gears.

I will put 21 ft pounds on the bearing and then have another push up on tension secure and pull the pin. When I look at the belt between the cams, its tight as it should be. When I rotate, a few revolutions, the belt is loose. It has about 3/4 of pushing down on the belt. I've replaced tension three times, used other belts to verify stretching, or number of teeth, etc.

I'm so lost. Can anyone put me in the right direction? 1999 Mitsubishi Eclipse OZ Rally, with 148k.

 

[BLACK'98DSM]

If you can easily slide the belt off the sprockets, that's when you should worry about it. There will always be more tension on the tensioner side, and a little "slack" between the crankshaft sprocket and exhaust cam sprocket. Also consider that shaving the head will naturally reduce that tension. I would normally shave the heads to their service limit for a compression boost. And it would result in the belt feeling loose on the exhaust side. I never had one come off or jump timing though.