Valves not closing

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JaredH
Tentative sideways sliding....
Tentative sideways sliding....
Posts: 37
Joined: Sat Apr 26, 2014 11:08 am

Valves not closing

Post by JaredH » Wed Jul 27, 2016 5:27 pm

Hi All,

I am doing a 1.8 swap with a motor from a '93 i believe (BP05 anyway). Long story short, the valves don't seem to be closing properly (leaving a few mm gap all the way around). Does anyone have any idea what could be causing this?
Background as follows which may/may not help with the diagnosis.

Picked up the motor on this forum, it hadn't been used for a while as the previous owner had built another motor.
I pulled the head, disassembled and had the head skimmed and hot tanked and the block decked (block wasn't disassembled).
I reassembled the head with new seals but the old parts.
Motor was cranking, sparking and getting fuel, but backfiring and not starting.
The valves seemed to be hardly moving, I thought it could be the HLA's from sitting s long having bled right down. Pulled them ut last night and they were squishy as, so swapped with the ones from my 1.6 (which had about 175psi at all cylinders prior to removal).
The valves now move as they should, except they aren't closing fully.

I've triple checked timing, and compression test is showing zero across all cylinders.

What could I have likely done wrong when rebuilding or what could be causing the problem??

Thanks in advance and sorry for the essay!

WideOpenThrottle
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Post by WideOpenThrottle » Wed Jul 27, 2016 5:38 pm

Cams re-fitted 180 degrees out by any chance?
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JaredH
Tentative sideways sliding....
Tentative sideways sliding....
Posts: 37
Joined: Sat Apr 26, 2014 11:08 am

Post by JaredH » Wed Jul 27, 2016 5:45 pm

I wish, lobes on #1 are facing outward at TDC.

There is mention on US forums of the HLA needing oil pressure to start working properly, which may be the cause but I wouldn't think so. And can't run the car to get pressure unless I sit there cranking for ages

JaredH
Tentative sideways sliding....
Tentative sideways sliding....
Posts: 37
Joined: Sat Apr 26, 2014 11:08 am

Post by JaredH » Wed Jul 27, 2016 7:33 pm

Could it be worn valve springs?

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