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66 Sprite oil psi/ Compression

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M

MCS

Jedi Warrior
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Hello,
It has been a while since I have posted. Jack provides so much entertainment I want to fly down to Florida and meet him. Thank you Jack for providing us with valuable information.
Mk3 Sprite 1098 eng
I also have low oil pressure, idle is 5-10 psi and during cruise around 25psi. When started it is 65 psi. The engine was rebuilt almost 30 years ago but only has maybe 2000 miles on it, and 1000 miles are in the last 6 months.(I am having so much fun driving know where) It runs great and seems to have good power. Just maybe I need only a new oil pump, which was never changed, not even sure exactly what was machined and replaced, the bill I found, but it has faded and is now blank. My plan is to drive this thing for at least another year before I do a complete paint from ground up. Thanks to Jacks experiences my engine is coming out next month and fixed and then run for a season before I strip the car completely.
Here are my compression numbers, what do you think, do I need to even touch the pistons and rings.
Cold numbers OAT 10 c
1-125 2-100 3-125 4-105 I only took 1 plug out each time. The next two readings are done with all plugs out eng at normal operating temp and throttle closed.
Hot numbers
1-135 2-128 3-140 4-138 all plugs out throttle closed
Hot numbers, I squirted some oil into each plug hole
1-150 2-140 3-160 4-155
I will be doing all the work myself, was hoping to go with a Kent cam (276) I think is the best choice. Using tons of sealant ( Jack has scared me) just ordered a couple tubes of Hylomar sealant. It does currently like to leave a small happy to see you puddle of oil. My brick driveway is taking a beating.
I will be checking all bearings etc when I tear the motor down

My other concern is the transmission works ok but is noisy in first gear. The noise is when I pull high revs, can’t tell you the number my tac still does not work thanks to pertronix ignition. Also when I release the clutch I often get a chatter type of vibration. I am using 20w 50 castrol oil. The transmission came out of a 1971 midget with a 1275 I think. Is the noise/chatter normal or should I order a rebuild kit from VB. Could the chatter be a bad flywheel.
Has anybody used there rebuild transmission kits.
Thanks Phil
I am sitting in the hotel in St. John’s Nfld, watching the dead bears blow by my window; a calm day here is when the winds are only 30kts. Home by noon Friday. I need to go for a drive sure hope the snow has melted
Cheers
fall pics
https://i188.photobucket.com/albums/z234/ECAM_2007/P1000664.jpg
https://i188.photobucket.com/albums/z234/ECAM_2007/P1000663.jpg
https://i188.photobucket.com/albums/z234/ECAM_2007/P1000662.jpg
 
Tranny's are always noisy in first gear. Difference in the way the gears are cut. Compression numbers aren't great but at least fairly consistent, #2 might be suspect. I've got similiar #'s in the 1098 that is installed in Bugsy my '68 Sprite. Runs pretty good but leaves 5 drops as a calling card whenever he is parked. Cardboard is cheap. I'll let others comment on oil pressure.
 
Thanks Jim.
I thought first gear noise is normal, how about the chatter, any coments
Phil
 
Hi Phil

I would shim up your oil relief value and see if you can get a little more oil pressure.

Mark
 
Chatter is caused by several things but the easyest to fix and check are worn engine and tranny moter mounts or a loose mount. Double check that you have all four bolts in the tranny mount, and do replace all when the engine is out. Cheep insurance and rubber does not last forever.

The only other real cause of chatter is worn out springs in the pressure plate and I do not think that is even a possibility as long as the clutch is working well and grabs well otherwise.
 
Oil pressure relief valve is a nut on the site of the engine. Look in the MOSS or VB Catalog and you can see what they are talking about. Spring might just be well worn giving low pressures. Or it could really have those types of problems.
 
Hello Mark,
I tried the shim, I used a 9/16 ball bearing. It helped but not enough. The dam nut was very hard to get back on. I measured the spring length etc it was all good.
Thanks Phil
 
Jack,
I wondered if I had a bad tranny mount. Climbed underneath last night, well the mounts that are there look old, hard to tell if they are broken. What surprised me is I am missing the bottom rubber mount. So I would say that is probably where my chatter originates from. It is -5c today so not to motivated to take the mount out.
Thanks Phil
 
Still looking for some coments on the compression numbers, what do you guys think. I have read somewhere anything over 100 is ok.
Phil
 
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