Thread: rotary valve clearance
01-29-2015, 11:58 AM #1
rotary valve clearance
last summer Ive had issues with very hard to no start while on the water with my 99 gsx rfi (787) with a barely broke in engine rebuilt by ses
so reading that too much clearance on the rv could cause hard starts.
so i pulled the o ring off to check for clearance and get a perfect .012 checking it in several positions but on the mag port is .012 at 9, 12, 6 o clock positions
but at 3 o clock i get .015. which is a hair out of spec. see image that points it out.
don't know if it necessary to check it there or not. some input would be greatly appreciated.
ps it has a new rotary valve and the cover was resurfaced by ses.
01-29-2015, 03:44 PM #2
.015 will start and run just fine. Have you hooked to Buds or Candoo and set the TPS? TPS setting is where i have found the majority of my RFI problems to be rooted.
01-30-2015, 01:29 AM #3
yes i even installed a new tps and reset it with my candoo pro. of course after loosening the throttle cable so that it is all the way closed. i ohm tested all the sensors as well as scanned them with the candoo and no codes. replaced with a 4 tec regulator from osd parts. new fuel pump and filters, new injectors and passed the drip test..
i also replaced the fuel pressure regulator just recently as testing the old one with a gauge showed 58 psi, the dropped 50% sitting for a half hour, the new one only drops maybe 5 psi and stays there over night. so i'm hoping that will be the fix.but wont know till it warms up outside. thoughts?
01-30-2015, 10:09 AM #4
Have you trimmed your spark plug wires? Have you done recent compression check? Double checked the rotary valve timing? Sounds like you have covered all of the typical RFI demons... it's got to be something simple now...
01-31-2015, 01:52 AM #5
yep trimmed wires, compression is 148 and 150 psi rv timing is good. like i said, i haven't been able to test the ski sense i replaced the fuel pressure regulator so hopefully it is fixed at least very narrowed down. thanks again. will post here when the weather warms up and can take her out.
02-12-2015, 03:03 AM #6
02-13-2015, 01:43 AM #7
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