Compression test battle. 73 Imperial.

Boydsdodge

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First. There is no way a sane person is doing a hot compression test on a Fuselage Imperial. By the time you get the plugs out your engine would have lost 2/3rds of its running heat, then by the time you have done the left side you would be close to room temp. Also blistered hands and arms along the way.
I started with a room temp engine, all plugs removed, throttle open and a battery charger connected to battery. I find out half way that the battery charger is not charging or keeping up. I had to go back and do a few over with new battery charger hooked up and after a while of charging.
I did dry and wet. 5000 miles for plug install, last few drives were in urban traffic, an hour at a time at least.
Looks like the plugs are getting a bit wet with oil and fuel additive. (the outboard oil is all that has been added.) I would say too much outboard oil, and seals leaking. Also the gold on threads is copper anti seize, I thought these plugs might be installed for a while. The plugs also are a bit cool, could go hotter. Timing looks good. Let me know what you see.
Tux needs heads. I have a set of 452 heads at friends machine shop, after he gets the heads cleaned and disassembled I will bring home and do some port matching and clean up. I will do same with intake and exhaust.
While the top end is apart a new chain and gears will join in with the fun. What are your thoughts on Cam change? Ya or Na with thoughts.
More plug pics in second post.

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nothing an engine rebuild won't cure...you've got low compression on 2 and even lower on 8...and signs of burning oil...whether that oil is from the rings, guides, or the (why?) outboard oil i don't know...so you could rebuild the heads and hope for the best and see if it improves the oil situation or go for the whole 9 yards now...depends on your financial situation and abilities
 
Compression numbers don't look too bad. Obviously #8 has some issues, from the top and bottom of things.

One thing bothers me is the number of plugs that look like they have "sand" on them. Allegedly that is supposed to mean "dirty air filter" that's letting things through that should not be let through. Just looks unusual to see that much "grit" on so many plugs.

Personally, you can clean the plugs in carb cleaner and then knock off any "deposits" on the center electrode and such, then dress the center electrode with a point file, gap to your desired spec, then put them back in.

It will be interesting to see where the oil in #8 has migrated from.

CBODY67
 
nothing an engine rebuild won't cure...you've got low compression on 2 and even lower on 8...and signs of burning oil...whether that oil is from the rings, guides, or the (why?) outboard oil i don't know...so you could rebuild the heads and hope for the best and see if it improves the oil situation or go for the whole 9 yards now...depends on your financial situation and abilities
In another forum, outboard motor oil is used as Maravel Mystery Oil or "top engine lube" in the gas. The guy who mentioned it in the other forum raved about how well it worked to keep things working well. 1oz per 5 gallons of gas. He was using one of the synthetic products.

Enjoy!
CBODY67
 
In another forum, outboard motor oil is used as Maravel Mystery Oil or "top engine lube" in the gas. The guy who mentioned it in the other forum raved about how well it worked to keep things working well. 1oz per 5 gallons of gas. He was using one of the synthetic products.

Enjoy!
CBODY67
I’ve been raving about it for years, marine 2-cycle TC-W3. It’s to counter the negative effects of ethanol.
 
I think one once per 5 gallons might be too much. I think some of the deposits are from the 2-cycle oil. But it will need the heads rebuilt. I am thinking the rings are ok as the readings did not change much and this was a cold test.
 
I think one once per 5 gallons might be too much. I think some of the deposits are from the 2-cycle oil. But it will need the heads rebuilt. I am thinking the rings are ok as the readings did not change much and this was a cold test.
Honestly I can say that I’ve been using it without missing a fill-up and likely at a higher rate than 1oz per 5 gallons as I don’t dispense pre-measured at the pump. I’ve not seen deposits like that on my plugs.
 
What is your EGR doing, blocked or still trying to do it's thing?
You have oil intrusion.
Does this car do a lot of short trips?
 
EGR vacuum line is blocked, I do want to block the EGR when I do the head work. Yes it has been doing some 1 hour max slow drives, just had a tank of fuel go thru in slow urban traffic, 25/35 mph max. It gets lots of highway runs during the summer show season.
Here are pics of the Champions I removed 5000 miles ago. I think the Champions were in for maybe 1500 miles.
I have always known number 8 had a mis fire, I finally made time between clients to get some of my maintenance caught up.

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