R69S poor compression
Posted: Sun May 28, 2023 3:59 pm
Hello everyone
I just rebuild R69 engine but modify to R69S and did 1500mile run in.
new R69S piston new camshaft (RS stamped) new lifter new timing gear set
restored R69 crankshaft (SALIS did it perfect )
very easy to start but the spark always serious dark poor idle and very weak at low rpm.and always backfire
I tried the timing light to check at idle.it just on S mark and up down around 1mm.
so i checked the cylinder pressure.only 100 psi after 6-7 hard kick.and intake clearance around 0.06in
than i adjust clearance to 0.11in and check pressure.it go up to 155psi you can feel the kick pedal become
harden
Ride with 0.11 intake clearance no any backfire and more power at low rpm.
try adjust to 0.16in than first kick already 80psi after 3kick already 160psi.
and i try to did the leaking down test it is good.valve without any leaking.
I change another R69S cylinder head on and all the same.
Checked the timing gear line is matched.but it like camshaft timing wrong.
its R69S 320degree camshaft with RS stamp.is that possible camshaft issue?
Wish any one had any experience like this and tell me what's going on?????
I just rebuild R69 engine but modify to R69S and did 1500mile run in.
new R69S piston new camshaft (RS stamped) new lifter new timing gear set
restored R69 crankshaft (SALIS did it perfect )
very easy to start but the spark always serious dark poor idle and very weak at low rpm.and always backfire
I tried the timing light to check at idle.it just on S mark and up down around 1mm.
so i checked the cylinder pressure.only 100 psi after 6-7 hard kick.and intake clearance around 0.06in
than i adjust clearance to 0.11in and check pressure.it go up to 155psi you can feel the kick pedal become
harden
Ride with 0.11 intake clearance no any backfire and more power at low rpm.
try adjust to 0.16in than first kick already 80psi after 3kick already 160psi.
and i try to did the leaking down test it is good.valve without any leaking.
I change another R69S cylinder head on and all the same.
Checked the timing gear line is matched.but it like camshaft timing wrong.
its R69S 320degree camshaft with RS stamp.is that possible camshaft issue?
Wish any one had any experience like this and tell me what's going on?????