---------------------------------------------------------- Yak-List Digest Archive --- Total Messages Posted Wed 04/28/21: 2 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 08:59 PM - Re: Housai engine question: compression check (Justin Drafts) 2. 09:14 PM - Re: Re: Housai engine question: compression check (Larry Pine) ________________________________ Message 1 _____________________________________ Time: 08:59:37 PM PST US From: Justin Drafts Subject: Yak-List: Re: Housai engine question: compression check Good evening all- A conundrum for you Housai engine experts; I need some advice to go fwd. Doing the compression check today, I hit a weird wall. With a partner I was checking cylinders starting with #1 at top, going CW when viewed from cockpit. All #'s were good (avg 75/80 psi), until I got the last cylinder, #2. We got 0 psi on the pressure gauge. Checking the pressure tester/gauges/fittings/hose, all are fine and perfectly functional. So we double checked the previous cylinder, which had just 10 min prior tested at 74/80 psi.... now it also showed 0/80 psi. ?? No obvious air leaks from oil breather, carburetor, or exhaust stack; no oil evident at bases of the cylinders; the exhaust and intake stacks are good condition. I had flown the plane earlier in the day w/o any negative indications. Pulled the valve covers off to find the rocker arms, springs, etc in great condition, doing their job when we slowly turned the prop thru by hand. Stuck valves? We tried the "rope trick" to slip a nylon cord into the cylinder thru the open sparkplug hole, then gently run the piston up to TDC to try to reseat the possibly stuck-open valves. As yet, no help. Fishing for advice & thoughts... what are we missing? I've never seen a 0/80 psi reading... a bad piston ring or bad valve, should have SOME psi indication 30~60psi. Thoughts? Pointers? Thanks--- Justin Drafts N280NC ________________________________ Message 2 _____________________________________ Time: 09:14:53 PM PST US From: Larry Pine Subject: Re: Yak-List: Re: Housai engine question: compression check Clogged secondary gauge. If you collider off the gauge exist and open the v alve between the two gauges, do you get 80/80? If not the second gauge is h osed. Sent from Yahoo Mail for iPhone On Wednesday, April 28, 2021, 20:58, Justin Drafts wrote: Good evening all- A conundrum for you Housai engine experts; I need some advice to go fwd.Doi ng the compression check today, I hit a weird wall. With a partner I was checking cylinders starting=C2-with #1 at top, going CW when viewed from cockpit.=C2-All #'s were good (avg 75/80 psi), until I got the last cylinder, #2.=C2- We got 0 psi on the pressure gauge.=C2 -=C2- Checking the pressure tester/gauges/fittings/hose, all are fine and perfect ly functional.=C2- So we double checked the previous cylinder, which had just 10 min prior tes ted at 74/80 psi.... now it also=C2-showed 0/80 psi. ??No obvious air lea ks from oil breather, carburetor, or exhaust stack; no oil evident at bases of the cylinders;=C2-the exhaust and intake stacks are good condition. =C2-I had flown the plane earlier in the day w/o any negative=C2-indica tions. Pulled the valve covers off to find the rocker arms, springs, etc in great condition,=C2-doing their=C2-job when we=C2-slowly turned the prop th ru by hand. Stuck valves?=C2- We tried the "rope trick" to slip a nylon cord into the cylinder thru the o pen sparkplug hole, then gently run=C2-the piston up to TDC to try to res eat the possibly stuck-open valves.=C2- As yet, no help.=C2- Fishing for advice & thoughts... what are we missing?=C2-I've never seen a 0/80 psi reading... a bad piston ring or bad valve, should have SOME psi indication 30~60psi. Thoughts?=C2- Pointers?Thanks--- Justin DraftsN280NC ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message yak-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/Yak-List.htm Web Forum Interface To Lists http://forums.matronics.com Matronics List Wiki http://wiki.matronics.com Full Archive Search Engine http://www.matronics.com/search 7-Day List Browse http://www.matronics.com/browse/yak-list Browse Digests http://www.matronics.com/digest/yak-list Browse Other Lists http://www.matronics.com/browse Live Online Chat! http://www.matronics.com/chat Archive Downloading http://www.matronics.com/archives Photo Share http://www.matronics.com/photoshare Other Email Lists http://www.matronics.com/emaillists Contributions http://www.matronics.com/contribution ------------------------------------------------------------------------------------- These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.