Profile Picture

1955 Y block 272 smokes after 5 minutes of running?

Posted By Bill Pabon 7 Years Ago
You don't have permission to rate!
Author
Message
Bill Pabon
Posted 7 Years Ago
View Quick Profile
Hitting on all eight cylinders

Hitting on all eight cylinders (12 reputation)Hitting on all eight cylinders (12 reputation)Hitting on all eight cylinders (12 reputation)Hitting on all eight cylinders (12 reputation)Hitting on all eight cylinders (12 reputation)Hitting on all eight cylinders (12 reputation)Hitting on all eight cylinders (12 reputation)Hitting on all eight cylinders (12 reputation)Hitting on all eight cylinders (12 reputation)

Group: Forum Members
Last Active: 7 Years Ago
Posts: 5, Visits: 15
New to the forum and I have no experience at all with the "Y" block. My daughter 23 fell in love with a 55 4 door custom line and the father/daughter project commenced. The car appears to have been a "work in progress" when we bought it from an older gentleman who was no longer able to work on it because of health issues. Before we could get any details about what had been done to the car he had suffered a stroke and could not recall what had been done. So we took a chance on it resolving that the engine appeared to have fresh paint and fresh oil and the coolant was nice and clean in the radiator. Original "oil bath" breather was still in place etc...

After some research and trial and error we managed to get it to start and run after chasing down a 6 volt generator that was missing and new wires etc.. With new points, plugs installed and rebuilding the carb. New gas tank and fuel pump - it starts and runs just fine until the engine gets good and warm and we start to get bluish smoke after 5 to 6 minutes of running.

We did not check the actual engine compression for each cylinder because it did start up after we sprayed engine oil into each cylinder bore to lube everything in case it was dry and after the initial start up smoking it quit smoking. The oil pump is pumping oil into the valve galley and valve springs. Could it be that the valve guide seals are failing?( umbrella seals on valve stems - really can't see into the spring area)

We also did not change or fool with the thermostat for fear of a bolt breaking off etc.. We also did not change any other filters - did noticed it has a down draft tube of some sort with a "can" on the tube? PVC? Help! We were trying to avoid pulling the engine for a full rebuild. If we have to we will. We are going to buy a good compression gauge and start all over and try to find a manual to determine what is acceptable compression readings per each cylinder. Any suggestions will be much appreciated!

Thanks,

Bill in Georgia


slumlord444
Posted 7 Years Ago
View Quick Profile
Supercharged

Supercharged (2.3K reputation)Supercharged (2.3K reputation)Supercharged (2.3K reputation)Supercharged (2.3K reputation)Supercharged (2.3K reputation)Supercharged (2.3K reputation)Supercharged (2.3K reputation)Supercharged (2.3K reputation)Supercharged (2.3K reputation)

Group: Forum Members
Last Active: Yesterday
Posts: 1.2K, Visits: 131.7K
A compression check is a good place to start. Is tempreature gauge working? You need to be sure it is not overheating.
oldcarmark
Posted 7 Years Ago
View Quick Profile
Supercharged

Supercharged (6.0K reputation)Supercharged (6.0K reputation)Supercharged (6.0K reputation)Supercharged (6.0K reputation)Supercharged (6.0K reputation)Supercharged (6.0K reputation)Supercharged (6.0K reputation)Supercharged (6.0K reputation)Supercharged (6.0K reputation)

Group: Forum Members
Last Active: 3 Weeks Ago
Posts: 3.6K, Visits: 32.2K
The Tube-Can on the side is the Road Draft Tube for Crankcase Ventilation. Air go us in the Oil Fill Cap and exhaust Fumes out the Drft Tube. There is a Filter in there which is accessible by taking the Can off.

http://forums.y-blocksforever.com/Uploads/Images/a82cee8f-be33-4d66-b65d-fcd8.jpg  http://forums.y-blocksforever.com/uploads/images/339ed844-0bc3-4c73-8368-5dd3.jpg
2721955meteor
Posted 7 Years Ago
View Quick Profile
Supercharged

Supercharged (2.1K reputation)Supercharged (2.1K reputation)Supercharged (2.1K reputation)Supercharged (2.1K reputation)Supercharged (2.1K reputation)Supercharged (2.1K reputation)Supercharged (2.1K reputation)Supercharged (2.1K reputation)Supercharged (2.1K reputation)

Group: Forum Members
Last Active: Yesterday
Posts: 922, Visits: 187.7K
i would drain the eng oil,look for valve seal bits,also chang the filter. cut the old filter apart. use a wood chisel so no cuttings create fals alarm. at idel  the vacume will be high and if valve seals broken this could  be the issue . plus it is a cheap first look at what you have. ys are famous for vale seal disintegration. easy to fix with right tools. good luck
Ted
Posted 7 Years Ago
View Quick Profile
Co-Administrator

Co-Administrator (12.5K reputation)Co-Administrator (12.5K reputation)Co-Administrator (12.5K reputation)Co-Administrator (12.5K reputation)Co-Administrator (12.5K reputation)Co-Administrator (12.5K reputation)Co-Administrator (12.5K reputation)Co-Administrator (12.5K reputation)Co-Administrator (12.5K reputation)

Group: Administrators
Last Active: 2 days ago
Posts: 7.2K, Visits: 202.6K
As already mentioned, run a compression test to validate the condition of piston ring and valve seal.  Running a vacuum gauge on the engine may also give an indication of engine condition.  If the engine is a fresh rebuild, it may simply need to be broken in.  There’s a chance the exhaust system is full of oily residue from a previous engine and that will need to be simply burnt out by running the car for awhile.  I'll also add that the current engine may have sit long enough for the rings to stick in the piston grooves.  In this case, those rings may be loosened by simply heat cycling the engine a few times.  In a more worse case scenario, putting oil in the cylinders and then pressurizing each cylinder with air can help to free up the rings.

Lorena, Texas (South of Waco)


Bill Pabon
Posted 7 Years Ago
View Quick Profile
Hitting on all eight cylinders

Hitting on all eight cylinders (12 reputation)Hitting on all eight cylinders (12 reputation)Hitting on all eight cylinders (12 reputation)Hitting on all eight cylinders (12 reputation)Hitting on all eight cylinders (12 reputation)Hitting on all eight cylinders (12 reputation)Hitting on all eight cylinders (12 reputation)Hitting on all eight cylinders (12 reputation)Hitting on all eight cylinders (12 reputation)

Group: Forum Members
Last Active: 7 Years Ago
Posts: 5, Visits: 15
Ok so thanks for your input - going to do the compression test this Saturday. With my best research to date it looks like 130 psi is the number for a perfect scenario regarding each piston bore. What should be the minimum where I determine that the is the issue? Can I vary 30 psi per cylinder bore?

Again thanks for your input - much appreciated!

Respectfully,

Bill in Georgia
Bill Pabon
Posted 7 Years Ago
View Quick Profile
Hitting on all eight cylinders

Hitting on all eight cylinders (12 reputation)Hitting on all eight cylinders (12 reputation)Hitting on all eight cylinders (12 reputation)Hitting on all eight cylinders (12 reputation)Hitting on all eight cylinders (12 reputation)Hitting on all eight cylinders (12 reputation)Hitting on all eight cylinders (12 reputation)Hitting on all eight cylinders (12 reputation)Hitting on all eight cylinders (12 reputation)

Group: Forum Members
Last Active: 7 Years Ago
Posts: 5, Visits: 15
Hey meteor thanks for that tip - we will also look into that possibility as well! Will advise what we find along with the compression check.

Respectfully,

Bill in Georgia
oldcarmark
Posted 7 Years Ago
View Quick Profile
Supercharged

Supercharged (6.0K reputation)Supercharged (6.0K reputation)Supercharged (6.0K reputation)Supercharged (6.0K reputation)Supercharged (6.0K reputation)Supercharged (6.0K reputation)Supercharged (6.0K reputation)Supercharged (6.0K reputation)Supercharged (6.0K reputation)

Group: Forum Members
Last Active: 3 Weeks Ago
Posts: 3.6K, Visits: 32.2K
el
2721955meteor (7/13/2017)
i would drain the eng oil,look for valve seal bits,also chang the filter. cut the old filter apart. use a wood chisel so no cuttings create fals alarm. at idel  the vacume will be high and if valve seals broken this could  be the issue . plus it is a cheap first look at what you have. ys are famous for vale seal disintegration. easy to fix with right tools. good luck

I use a Dremel Tool with cutting Wheel. Cut the filter all the way around above the Base. Nice and neat.  

http://forums.y-blocksforever.com/Uploads/Images/a82cee8f-be33-4d66-b65d-fcd8.jpg  http://forums.y-blocksforever.com/uploads/images/339ed844-0bc3-4c73-8368-5dd3.jpg
Ted
Posted 7 Years Ago
View Quick Profile
Co-Administrator

Co-Administrator (12.5K reputation)Co-Administrator (12.5K reputation)Co-Administrator (12.5K reputation)Co-Administrator (12.5K reputation)Co-Administrator (12.5K reputation)Co-Administrator (12.5K reputation)Co-Administrator (12.5K reputation)Co-Administrator (12.5K reputation)Co-Administrator (12.5K reputation)

Group: Administrators
Last Active: 2 days ago
Posts: 7.2K, Visits: 202.6K
Bill Pabon (7/14/2017)
Ok. So thanks for your input - going to do the compression test this Saturday. With my best research to date it looks like 130 psi is the number for a perfect scenario regarding each piston bore. What should be the minimum where I determine that the is the issue? Can I vary 30 psi per cylinder bore?

It’s desirable for the cranking compression readings between all the cylinders to not vary any more than 10% between the highest and lowest.  My 272 runs in the 155-160 psi range on a cranking compression test.  That would mean no more than a 16 lb. variance between the lowest and highest readings.  Be sure to run the cranking compression test with the throttle blocked wide open.



Lorena, Texas (South of Waco)


Bill Pabon
Posted 7 Years Ago
View Quick Profile
Hitting on all eight cylinders

Hitting on all eight cylinders (12 reputation)Hitting on all eight cylinders (12 reputation)Hitting on all eight cylinders (12 reputation)Hitting on all eight cylinders (12 reputation)Hitting on all eight cylinders (12 reputation)Hitting on all eight cylinders (12 reputation)Hitting on all eight cylinders (12 reputation)Hitting on all eight cylinders (12 reputation)Hitting on all eight cylinders (12 reputation)

Group: Forum Members
Last Active: 7 Years Ago
Posts: 5, Visits: 15
Hey thanks Ted! For your input - should we expect higher compression on our 272 or is your engine been souped up with high performance components? Is my figure of 130 psi cranking pressure for a stock engine incorrect. Please advise!

Respectfully,

Bill in Georgia


Reading This Topic


Site Meter