1964 V6 Odd-Fire 225 Valve Seal Replacement

[vuldub]

Hello.  I have been reading on other sites that this engine did not have valve seals.  I cannot confirm this and would like to know as they are definitley available to order and  would like to replace them.  I need enlightening.  Thanks.

[Moses Ludel]

vuldub...Buick did not use valve guide seals on the "nailhead" V-8 or V-6 engines until the V-8s in 1966.  Then, the seals were only on the intake valves.  The Jeep Dauntless or Buick 225 is a nailhead design with the valve covers on a near level plane.  The later 231 engines, which are non-nailhead design, have canted heads and a different valve stem angle.  This calls for valve guide seals as found on conventional V-engines.

So, some do install seals on the 225 intake valves.  Others do not install seals at all.  Performance engines often get the valve guides machined to accept "PC-type" (Perfect Circle originated the design) spring seat seals that do not stand too tall and interfere with fully open valves and retainers.  On any engine, there must be enough room for seals when the valves open completely.  This would apply to PC-type or rubber umbrella/"mushroom" seals.

If you're reworking the heads with either new guides or silicone bronze valve guide inserts, the correct fit between the valve stems and guides should be close enough to minimize oil loss without guide seals.  If the valves and guides have wear or too much clearance, that's an issue.  There will be oil seepage at the intake valves and oil burning.

Buick discontinued its 225 V6 after 1967.  Kaiser/Jeep and AMC continued with this engine until 1971.  Jeep bought the tooling and began producing the 225 when Buick could no longer provide production engines.  By design, the 225 for Jeep's use was essentially a 1964 prototype, so the addition of valve guide seals in later Dauntless applications is questionable.  In fact, the popular gasket sets do not include umbrella seals, even for the intake valves.  

The 225 V6 in good condition was not an excessive oil burner.  If you note the angle of the valves and spring design, guide seals were apparently not a serious concern.  I have a 1971 copyright Jeepster factory workshop manual that still does not show or describe valve guide seals during cylinder head disassembly or assembly.  Note that the valve springs must be installed with the close winds toward the head casting (not toward the retainers).  Known as a progressively wound spring design, this would also help reduce oil accumulation at the valve guides.  Worth mentioning, rocker arms on rocker shafts limit oil spray and splash beneath the valve covers.

BOP Parts for vintage Buick, Oldsmobile and Pontiac engines offers this set of valve guides for the 225 V6:  https://www.bopparts.com/shop-parts/engine/individual-components/valves/1964-1965-1966-1967-buick-models-with-225-v6-engines-valve-guide-set-16-pieces.html.  These guides have no provision for PC-style spring seals and would require machining to accept aftermarket spring-type seals. 

All this raises the question of whether it's a good idea or not to add PC seals or even umbrella seals to a nailhead 225 V6.  If the seals don't get crushed due to spring height and clearance, would these seals restrict the nominal amount of oil that normally reaches the guides and valve stems?  Would the valve stems and guides wear out faster from oil starvation?

For a definitive answer, look for 1964, 1965, 1966 and 1967 Buick Special Service Manuals, the official GM/Buick factory shop manual.  See whether Buick added valve guide seals at any point during the 225's production.  Buick would have been more involved in the engine's design/engineering and warranty issues with plenty of experience here:  Nailhead V-8s were built from 1953 to '66;  the nailhead V-6s from the early sixties to 1967.  

My dog-eared copy of V6 Buick Power Source, the classic mid-eighties GM Motorsport Performance book, focuses on the 231/252 V6s.  The book does recommend machining Stage 1 and Stage 2 cylinder heads (231 V6 Even-Fire engines) for "Teflon" valve guide seals.  (These are essentially the spring seals originated by PC in the sixties.)  Teflon against the valve stem surface reduces friction while forming a good seal.  Keep in mind that the 231 and 252 even-fire engines have canted heads and stamped rocker arms (without long rocker shafts).  They are a more conventional "V" engine design, not an odd-fire nailhead.

Moses

[vuldub]

Moses.  Thank you for a great response.  I am taking this to mean valve seals would not be on this motor.  The right rear cylinder has a fouled spark plug - the other cylinders do not.  The engine blows blue on first start and progressively improves as it runs.  It will puff blue if stopped and idled for a bit, then accelerate away.  It also has the occasional back fire out the exhaust - scares the crap out of passengers....

[Moses Ludel]

vuldub...You're welcome...The answer was circuitous but provides some context.  Again, the final word on guide seals would be a Buick shop manual, which would end the bouncing around forums for everyone's anecdotes and opinions.  

From what you describe, the blue smoke on startup is most often valve guide wear.  The stopped and idle smoking can be general wear.  I would do a cylinder leak down test on each cylinder to check for valve seal versus piston ring seal.  My go to tool is always a cylinder leakdown tester, it's extremely versatile.  An inexpensive alternative is a simple air hold tool that would not give leak percentages but will indicate air noise and where that noise originates.  (Valve leaks are heard out the tailpipe and through the carburetor;  piston ring blowby makes an air noise at the crankcase, out the oil cap or dipstick tube.)  Set your air compressor line pressure to 60 psi as a starting point.  Increase to no more than "normal" compression pressure.  Each piston must be at exact TDC on its compression stroke for an accurate test:

https://www.amazon.com/Lisle-19700-Valve-Holder/dp/B000COC7ZU/ref=sr_1_1

There are less costly leakdown testers, too.  If you do much of this work, a leakdown tester will pay for itself quickly:

https://www.amazon.com/gp/aw/d/B0030EVL60/  [This is an industry standard from OTC.  There are listings at Amazon for testers as cheap as $28 to $40.  Read reviews before plunging.]

Backfire out the exhaust is carburetor or ignition related.  The odd-fire does require an odd-fire ignition distributor, cap and rotor.  Distributor cap contacts are "oddly" offset for the odd-fire's firing scheme.  Make sure these parts are correct, and if you're fortunate, you have a Delco-Remy distributor (ala Buick) and not the Prestolite that many Dauntless engines were plagued with...Consider this issue, too. 

The Prestolite (or any) shaft bushings wear out and cause wild fluctuations in ignition point dwell angle.  This can cause backfire.  Put a dwell meter on the ignition primary to see how stable the point dwell is.  A quick test is to set the breaker points on a cam lobe peak and push/pull the distributor shaft sideways.  Dramatic changes in the point gap would be shaft wear.

Moses

[vuldub]

Thanks again Moses.  

...Wes

[Moses Ludel]

Enjoy your project, Wes!  We've got plenty of cold weather for shop projects.  Our local region dipped to 0-degrees F (overnight low) over the last few days.  We were at a balmy 16 F. 

I find this time of year highly productive if there's a shop and heater.  Running heavy equipment years ago, November through April required dressing for extreme cold weather.  (-8 degrees F with a 30 mph wind in early December was one memorable swing/graveyard shift on the I-80 bypass fill at Winnemucca, Nevada.)  Extremes called for reverse fans with cowling, an option for the bigger machines...Calgary gets a long winter.

The flatfender is very cool.  Does it have the '64 225 V6 Odd-Fire conversion?

Moses

[vuldub]

Hello Moses.  This is a 1947 CJ2a flat fender, with a '64 225 V6 odd fire.   Its not mine - I have a '52 M38 with a '84 Buick V6 231.  This '47 belongs to my very best friend.  We have camped and travelled together for 30 years.  We both have truck campers and pull our jeeps (he trailers the '47) and I flat two my '52 - if you recall awhile ago I put a full floater rear end with hubs so I could flat tow and not challenge the transmission.  My friend has had to park his jeep for the last few years as they haven't been able to travel due to family circumstances.  Things changed this year and they are available relive our old camping adventures, but the '47 has been parked in a barn for several years and needs some TLC.  As my friend is up to his eyeballs in other jeep projects (he's building a Willys truck and and Willys wagon - retirement is good!), I offered to get his '47 on the road again.  My motives were purely selfish - if he has a running jeep, I get to run mine with him.  It hasn't been too difficult as it was a good driver before it hibernated in the barn.  I have flushed the fuel system (tanks, lines, carb), thorough check of fluids, working on a leak on the T18 transfer case, bleed the brakes and other general stuff.  It has always suffered from the valve leak issue so I thought while it was in my shop I would put new valve seals in.  I found some, ordered them, bought a buick repair manual, then got very confused about whether it even had valve seals.  That's when I reached out to you.  And thank you for your help.  I guess I will be making a necklace out of these new valve seals.  I won't be pulling the valves apart and putting new guides as you suggested - that's more than I wish to tackle on a friend's jeep.   It might be next years winter project for him.  I'll make sure I carry an extra quart of oil for him this summer.   Also thanks for the great tip on the distributor.  

Cheers.  Wes

[Moses Ludel]

Great to have friends at this level, Wes!  Pleased that the engine came from a Buick with a Delco-Remy distributor.  Though not failsafe, this distributor is much more reliable and easier to service than the Prestolite that Jeep outsourced. 

I see classic stuff in the pictures and am smiling.  The master cylinder is a tandem brake/clutch type used in '60-'62 Chevrolet and GMC trucks.  So the '2A is using hydraulic clutch linkage and twin swinging brake/clutch pedals, a common approach with this master cylinder. 

Smart to use molded radiator hoses, they're much easier on the radiator necks.  The ballast resistor is essential for the coil.  The early (1964-65) Buick 225 V-6 has a Rochester one barrel carburetor.  Most Jeep and later (1966-67) Buick 225s use the Rochester 2G type two barrel.  Yep, it's a '64 engine!

If the engine is smoking on start-up and a coast down under compression, followed by opening the throttle, suspect worn valve guides.  If smoking under load or acceleration, rings can be involved.  The new valve guide seals (if umbrella type) might reduce the amount of oil running down the intake guides, a stopgap solution though time consuming to install.  If the engine is running okay with reasonable compression at each cylinder and no spark plug fouling, your idea of carrying a quart of oil works!

Enjoy your outings with friends, that's what four-wheeling should be about!  Campouts must be great at Alberta and the Canadian Rockies.

Season's Best,

Moses