08 D7 low compression

[signdude]

I pulled my sled out of storage today. I am getting only 50-60 lbs of compression from both of my cylinders. It ran fine late last season.

I pulled the cylinders. Ring gap is fine. No damage. Pistons were replaced in 2011. I am going to have cylinders checked for trueness?.

Any other suggestions?

 

[trench]

Your compresion test should have been performed after engine warm up.
Always good to check your compession tested on a good motor making sure it's reading correct.

Also make sure you take both plugs out , hold throtle wide open and pull 4-5 times as hard as you can until gauge needle stays at max.

My 700 reads around 130 both sides.

 

[PaulAnd]

Does it run? How well does it run? Redo the compression test with another gauge/tester, bet the gauge is faulty.

 

[Kraven]

I pulled my sled out of storage today. I am getting only 50-60 lbs of compression from both of my cylinders. It ran fine late last season.

I pulled the cylinders. Ring gap is fine. No damage. Pistons were replaced in 2011. I am going to have cylinders checked for trueness?.

Any other suggestions?

Rings might simply be "stuck"

Do they seem gummed up at all?????

 

[sledneck_03]

Crazy, I've heard of some problematic 700s but they are few. My dad tested by compression, i doubt he warmed it up but at 4600 miles i still got 120 lbs both sides.