and it wouldnt start. So after doing a little troubleshoot, i am getting fuel, i am getting spark, but i noticed the motor sounded as though it was turning freely, performed a compression check, i am not getting compression.

0-0-25-35

thats what the tests yielded. 4-3-2-1

I double checked the timing and it is dead on. I don't understand what is going on. Its a brand new motor. top and bottom. If it makes any difference i am using first gen b16 cams and its a 94 gsr motor. Im using the cams to for a back to back dyno comparison with a set of itr/ctr cams. next step is leak down test but thought i could get some feedback.

thanks

 

well a leakdown is next. see where the compression is going.

you are 100% sure the belt is on correctly?

 

10000% sure, ive done it at least 30 times and this has happened to me once before but i was able to notice right away.

this is what i did to make sure...

i spun the motor until #1 was at tdc(by looking into the cylinder) and the cams ticks where facing each other, the "up" was pointing up, and the notch on the sprocket that comes from the crank was lined up with the notch on the oil pump.

 

yeah I would definately be doing a leakdown... then you will know if its in the head or what.

could be the valves maybe not closing completely... did you adjust the lash after the cam change?

 

i was about to say valve lash as well

 

Those are horribly bad #'s. Hate to ask but are you sure you did the compression test correctly and that the gauge is good?

 

i have not, and was about to yesterday but my power went out and it was getting dark.

being that these are less aggressive cams wouldnt the valves would want to close faster?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by White Smoke &raquo;</TD></TR><TR><TD CLASS="quote">Those are horribly bad #'s. Hate to ask but are you sure you did the compression test correctly and that the gauge is good?</TD></TR></TABLE>

Positive.

 

anybody know if valve lash would cause this?

i had gsr cams in it before, then i went to first gen b16 cams. i cant figure this out.

also anyone in oc area wanna let me borrow a leak down tester?

 

if the head was completely dis-assembled and then re-assembled you probably need to do a valve lash adjustment. i remember reading on here a while back someone had the same problem you are, and it was because the rockers were out of adjustment.

 

Does the head have aftermarket valves or a valve job ?
I have seen numerous setups have issues with aftermarket valve jobs/port jobs not sealing up their valves properly etc....

Get a leak down tester, sounds like loss through the valves.

 

the head is built. valves/springs/retainers and guides were replaced.

as i dont have a leak down tester i will do a valve adjustment and see if it gets better. i just dont see how it would cause the valves to stay open, unless they were way way out of spec, but i hooope so.

 

VALVE LASH ADJUSTED AND FIXED.

although....

this is what my compression is like now.

after about 4-5 cranks

4-1

205 210 180 190

but it was very noticable that 4,3,and 1 had very hard pulses. 2 wasnt that hard. and it kind of struggled to get to 180.

???

 

Has the motor been ran at all? Or is it still all brand new while your performing these tests? Have the rings had a chance to seat yet?

 

yeah break her in, then post the new compression numbers.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by SpoolnG2 &raquo;</TD></TR><TR><TD CLASS="quote">Has the motor been ran at all? Or is it still all brand new while your performing these tests? Have the rings had a chance to seat yet?</TD></TR></TABLE>

x2!! Let that thing warm up!!

 

Like previously said, let the motor break in for a little while. Drive it for about 20 miles or so, let it cool down completely, then re-do the valve adjustments.

Then do your tests again.

 

lol totally forgot about the whole new motor thing.

if all electrical is fixed this weekend i will be headed over to church the following weekend for a tune. oh and the major oil leak at the back of the block. i had the motor running for about 30-45 seconds and the damm thing spit out about 1 quart of oil. looks to be coming from the oil filter. should be easy to fix.

thanks for your help fellas.

 

No problem, hope all works out for ya.