#1
IP: 75.82.181.203
|
|||
|
|||
2 cylinders - 0 compression :/
Well now I know why this thing would not run after a full ignition tune up despite having run ok 3 days before (now i think it was alway on 3 cylinders as it huffed and revved slowly like a diesel!)
I have the manifold off and sprayed penetrating lube onto each of the 4 valve stems - What are my next steps? The valves seem to point up so how do I get them out for a steel wire brush? Do I need to remove the top head? Sorry never seen the inside of one of these - Could it be stuck lifters? Any advice welcome! Cyl 3 and 4 show 85 and 90 psi respectively.. *** Since its 1 and 2 that are dead I highly suspect a blown head gasket after thinking about it more clearly. Last edited by CamaroMan; 10-21-2017 at 03:23 PM. |
#2
IP: 24.152.132.65
|
||||
|
||||
I propose removing the valve cover and observing the motion of the valve stems for #1 & #2 cylinders as the engine is cranked before jumping to any conclusions. Look for two that do not remain in contact with the lifters as they drop.
edit: It's becoming apparent to me that you might not have the Moyer Marine Service and Overhaul manual. It should be required reading for A-4 owners and mechanics alike, would be an excellent guide to an old technology flathead engine that is rarely seen anymore.
__________________
Neil 1977 Catalina 30 San Pedro, California prior boats 1987 Westsail 32, 1970 Catalina 22 Had my hands in a few others Last edited by ndutton; 10-21-2017 at 03:44 PM. Reason: clarification |
#3
IP: 174.237.9.199
|
||||
|
||||
Quote:
Neil was reading my mind. You really need to get the MMI "Bible" ASAP. We're all very glad to answer questions and help troubleshoot on this site but the bible is required reading around here.
__________________
-Jerry 'Lone Ranger' 1978 RANGER 30 |
#4
IP: 73.129.213.235
|
||||
|
||||
It has also happened that the lifter can get stuck. When this
happened to me, the valve moved freely, but the lifter stuck at the top of its cycle. 0 lbs of pressure. I had to remove and polish it before things worked well. James |
#5
IP: 75.82.181.203
|
|||
|
|||
thanks all - yes I have a pdf for the atomic - i was going to do exactly that 2moro (my wife usually accompanies me on outings lol except today)..
I need to have another look at the motor re valves/lifters - but judging from the build up on some valves i think a valve clean up / head gasket replacement wd not be a bad idea! this thing is OLD! At the very least it would mean a fresh start re top end - instead of trying to bandaid sticking valves form here on forward, in deep early is better than in deep down the road adrift at sea! Yes I had the same issue on a diesel truck i bought last yr, one lifter was stuck (exhaust) - NOT a pleasant sound. I too sanded out the bore (it wasnt the lifter - i checked). Been running tops since - |
#6
IP: 24.152.132.65
|
||||
|
||||
We weren't talking about the old Universal manual if that's the pdf you have. There's a big difference between it and the manual created by MOYER MARINE.
__________________
Neil 1977 Catalina 30 San Pedro, California prior boats 1987 Westsail 32, 1970 Catalina 22 Had my hands in a few others |
The Following User Says Thank You to ndutton For This Useful Post: | ||
sastanley (10-22-2017) |
#7
IP: 71.178.91.146
|
||||
|
||||
Yeah, you need this manual if really want to do any work on an A-4...it is the bible.
__________________
-Shawn "Holiday" - '89 Alura 35 #109 "Twice Around" - '77 C-30, #511 with original A-4 & MMI manifold - SOLD! (no longer a two boat owner!!) |
Thread Tools | |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
no compression from two cylinders | heinz | Troubleshooting | 7 | 08-25-2016 08:58 PM |
Zero Compression cylinders 3+4 | T27_478 | Troubleshooting | 26 | 07-30-2013 03:57 PM |
Low Compression on middle two cylinders | GMcK106 | Troubleshooting | 23 | 07-19-2013 08:50 AM |
Water in cylinders and no compression | gregt | Troubleshooting | 4 | 07-26-2010 12:21 PM |
Lower compression in non-adjacent cylinders | rods a4 | Troubleshooting | 4 | 08-24-2007 02:40 PM |