250 HPDI compression

[kmoore]

I just had my oil pump changed out thanks to the info I obtained on this board. The dealer checked the compression and recorded the info for me. My question is this, is 100,101,100,98,102,101psi normal for an 04 250HPDI with 93 hrs on it? They said it was but I would like another opinion.

[HAWK18]

I just had mine done as well and the compess was 110-115 and my motor is also a 2004 250 hpdi with 110 hrs on it hope this helps....

[kk4iz]

My 06 was 120 - 122 when I had my oil pump check a few weeks ago.




Modified by kk4iz at 7:37 PM 10/17/2007

[5 keepers]

Call Yamaha to find the spec range. Good luck.

[Skeeter Madness]

Mine was 120 on all 6 when I had my oil pump changed recently. I have an '06 though.

[vafishing]

I think they should be around the 120s on all 6 but that will only matter if it is done with a calibrated compression guage. The bigger thing to look for is if the numbers across all six are fairly consistent. if say 5 are around 119 and the other one is at around 100 that could be a problem.

[kmoore]

Thanks for the input. I have been running Seafoam at 1oz to 10 gal. I was told by the dealer that I should probably be running ringfree. I have about 1/4 tank of gas in both sides with Seafoam in it. Will it hurt to fill the tanks and start running ringfree now or should I drain tanks and not mix the 2 products?

[vafishing]

I run both eith no problems. Ring free with every time I put gas in and Sea Foam every month and a half to two months to clean things up.

[JeremyL]

Mine were 120-125 on all! 06 225 HPDI!

[Jason Hale]

That is fine with all 6 being that close. All mechanics and tool shops will tell you that no 2 compression guages will read exactly the same. The actual compression number is not as important as the relation of the cylinders to each other. That being said you can check and engine with 2 guages and get reading of let say 122, 120, 118, 120, 121, 119 on one guage and then 110, 108, 106, 108, 109, 107 on the other guage. Now you can see that the actual numbers are different, but their relation to each other is the same. Hope this helps out, we run into this at times when checking out engines in the shop.

[kmoore]

Thanks Jason,
I will check it myself tonight. Is there any trick to this, like holding the throttle open while turning it over? I just worry that mine seem lower than most others.
Ken

[macinckirk]

Just take all the plugs out and turn it over, Mine reads diff on my guage then its does at the shop on there guage also by about 5psi

[Jason Hale]

That is it. Again, go more by the difference in the cylinders than the actual #. Now of course if it reads 50 or something then there may be a problem, but if your guage is reading 100-120 or so and all are within 10% of each other you don't have a problem.

[kmoore]

I just checked with my guage and all read 110-112 except one. It was 102. I still have some YES warranty left, and it runs great so I guess I'll quit freaking out, for now.