Pontiac OHC-6 Tear Down - Top End Failure 

in 69 the sprint 6 made 230 hp which is very impressive for a 6 cylinder in 1969, especially considering the base model 326 V8 only made 250! in 1993 the Ford 302 that came in the mustangs only made 225hp that little sprint was making five more horsepower with 2 less cylinders and 24 years prior! that's pretty impressive!

My dad bought a 67 tempest in about 1969 and that 6 cylinder was a hot little engine. Very fun car to drive. I used to get up in the middle of the night and sneak it out of town and drive the hell out of it. I didn't have a driver's license yet. I've always loved that car and would love to have one of my own. I'd definitely want a 6

Cam failures were extremely common for this engine back in the day. The oils were just not good enough, and lack of timely oil changes sure didn't help. Also the TORX bolts, that was the first time we saw anything with those. The tool trucks in the 60's didn't have them, we had to chisel the bolts loose...ugh!

Your a different breed Girl…And it’s Awesome. Always an Adventure. Keep up the good work, can’t wait for the next step !! 🤘🏻😎🤘🏻

Looks like the same wear on the cam and followers that happened to my Pontiac OHC . Glad you did the teardown, a made the effort to diagnose the noise !

Great Program, the young lady is very well versed in her knowledge of engines and there direction is very well grounded. Thanks for picking this car because I had been interseted in the grand prix not realizing that the was before the grand prix became popular.

Just watched your video for the first time I'm a retired mechanic and drive a 69 firebird, my wife also has a 69 bird as well mine is a 5 speed manual her's is a 4 speed auto I also drive a 58 Ford Fairlane manual transmission ,if you can learn to drive that Camaro like a motorcycle meaning the shifting it won't beat you up and it will be fun to drive,injoy Ed the content.

Liv; I love your stuff, but that car would be 1000% better with the ohc 6!

Happy see the OHC6 being saved, but years ago when I looked at building one of these, I couldn’t find a cam anywhere. Of course this was before the interweb.

You make watching the video worth it! Keep up the great work

This car would be a the perfect recipient of the 4200 Atlas I-6. With a turbo, it would have plenty of power up top, it woud cruise long distance efficiently, it would run silky smooth as I-6s do, and it might even be lighter than the original engine. Richard has some videos on them.

Glad to see you guys are doing a collaboration with Richard!

It's a shame to park a car for a bad cam and rockers. Keep up the good work young lady.

liv, i see your a vice grip garage girl, awesome! your show and dericks are my favorite to watch, such good content on both

The OHC6 had oiling problems. The oil went from the (small) pump to the crank and rods first, and then to the head. As the bottom end wore, the oil delivery to the top end went down until, ultimately, there was insufficient pressure and flow to properly operate the lash adjusters and lubricate the cam. They were sweet, but were prone to failure between 80 and 120k miles. There is also the possibility of insufficient surface hardening of the cam and cam followers.

Pontiac always done major experiments....They had everything first... Electronic ignition etc.. Those are like the Ford cam followers on a 4.6 5.0 5.4 on that Pontiac... Awesome 😎 Thanks for sharing...

Hello Liv great job on going through the engine to find out what happened looking forward to watching your build on the car Wishing you well Take Care

Oh yes and ona financial note O’Reilly‘s auto parts commercial that you did ,,, it pops up on Matt’s recovery and off road towing channel it hits on almost every commercial spot on that channel nice thanks I’m talking about the one at Travis shop/ rental house !!! ,,,thanks BigAl California. Just look up Matt’s off road recovery and towing and you will see your self on the O’Reilly‘s auto parts commercial nice BigAl

I can remember here in Australia that General Motors-Holden very nearly used the Pontiac OHC six in our HR series Holdens in 1967 but it never eventuated, we kept using a six that was the same design as a Chevy 2 / Nova and in 1968 we used Chevrolet 307 and 327 small blocks in our Holdens as well with Holden designed V8’s as well as 350 Chevs in later models, we used a variety of GM designed engines and also used the Buick 3800 V6 in front engine rear wheel drive from 1988 in atmo and supercharged forms for many years in our Holden commodores and many variants of the LS small blocks into the late teens

Great video! Thanks for sharing. I came of age in the late 70s and early 80s and never even knew this engine existed. It's pretty cool, when you think about it, but we all wanted V8s, and a 6 cyl would have been completely out of the question.

Looks like rookie engine swapping day

I learned something. Didn’t know the cam was in the cover.

Close, in 1966 the monojet single barrel 6 cyl. was 165hp and the Sprint was 207. Also, the belt is adjusted by loosening the bolts holding the distributor/oil pump housing and sliding it up or down.

Pontiac Tempest - 2nd Generation 1964 - 1967: Base OHC Inline 6 (1Barrel Carb) 165 HP. Sprint Inline 6 (4Barrel Carb High Compression 207 HP) was a pretty respectful stock HP for it's time. One year later, the Ford Custom bone stock 302 V8 was 210 HP ... That's only 3 HP difference between a 6cyl & V8. There, was also a Tempest and GTO factory wagon. I think and agree, the inline 6 engine(s) should be tucked away in a safe place - replaced by a modern power plant where parts are easily available. If for only as a weekend show car, trailer it, but keep the factory Inline 6 in it for it's originality. (IMHO)

Yeah might have to weld up that bracket if not source able. Rockin the VGG Independence!

Holy smokes I had feeling when he said he was bolting on that bracket. Good thing it snapped when it did luckily no one was injured. One of those career ending mistakes. After hours in the shop and hard to explain gezz ..it's going to be legend Best Wishes 👍

Your Pontiac knowledge is impressive! Take notes, kids! The Liv is talking! 😎👍 Oh yeah. Tell Danny it's gallery not galley. A galley is the kitchen in a ship. Trust me. It took me a while of losing arguments before I finally caved into calling it a gallery. 🤣

bro I luv how u let her work on her on car so she can learn...boss move

Some fabulous cars in that garage, including the one you’re working on.

Jay Leno has a very similar car with Overhead Cam Six and it's a sweet car keeping the 6 and upgrading the brakes and suspension, incl. the steering box. John Delorean's idea to compete with the European cars he admired so much. He did also replace the cam rockers with hardened aftermarket's which were a problem on the original which also allowed him to raise the oil pressure as well and improve engine life. You should check out his video, these cars a kinda rare. Horsepower isn't really an issue as the handling and lighter weight make this a very fun car to drive.

I love your Pontiac and time to put that cool 455ci Big Block with dual carbs feeding that screw blower, so awesome 👍😎 ps/ be careful with those guys, they're reckless and ignorant with machinery. I've never seen such recklessness and unprofessionalism in my 30 years of doing engine work professionally. Thanks Liv!

Built a sprint engine! Such a cool engine for its time.

Yes please rake it . Ol drag racer trick shift weight to rear wheel's. And looks great 👍🤳

Hi Liv looks like a fun project now that you've sold the hot rod you can focus all your time on this one looking forward to the next video love the knowledge you have and the eagerness to learn is infectious take care

Hi Liv, this is very interesting to me. I have always wondered how it looked under that functionally animated designed cam cover. Thank you

That engine is a really rare pc.I hope you saved it,Pontiac guys would scoop it up.

i am a professional transmission rebuilder and shop owner, retired 2 years. your transmission is a Super Turbine 300, 2sp. most had a maple leaf embossed on the top of the bellhousing. they were made in Canada, and they were air cooled, that is the reason for the holes in the bell housing,,,,,,,,,,,,,,,,,,

Pretty cool engine. I haven't seen the inside of one of those since the early '70s when my cousin came back from Viet Nam and had to tear into the top-end like you just did. Pretty exotic design for then.

THE BEAUTY OF THE BELT DRIVE, IS IT WAS DESIGNED FOR THE FARMER TO FIX. CHAIN VS BELT, NOT ENOUGH HOURS IN THE DAY...😒😒😒 LOVE THIS EP.......

I'd take it, my Beaumont has a clapped out 250, and would love the upgrade, also I wish up here in Canada we could ditch the inner fender wells but they are a must to be inspected.

This car would be best served by returning it to its original motive power and running gear.

I knew that bracket was going to break

Ah....for the love ❤️ of de Pontiac 👌

The Independence shirt was almost a neat as seeing the inside of that cam cover.

OH!! memories 223378U607387 '68 F'bird Sprint OHC 4bbl,, put over 150K,,LOVED that car! Ordered new whilst stationed at DOW AFB, Bangor Me. 6 cross country trips. The distributor drive/oil pump carrier was the adjustment for the belt, it slid on a "ramp" up and down. The 230 had shorter cam finger lifters than the '68 250. I believe Clifford Research 6=8 still has parts avail.

My first car was a '69 Firebird I bought 1 year old for $1750. It had the basic 6 cyl engine and a 2 speed automatic, it wasn't fast but it was a nice driving car, top end was 105 mph.

SOLD ME, get rid of six, my Dad had one in our Garage for years came out of our 1966 Tempest. I thought it was one of the most beautiful looking cars back in 1972 when i was 8 years old. We took it all apart and scrapped it in 1974. Back then it was just a junk car. Lots of people didnt take care of cars back then. Heck in looked like yours and it was only 9 years old at the time, Paint fade and bondo. Dad tried his hand at do it yourself bondo from Grand Auto, never painting it. Someone hit it in a parking lot and drove off taking out the quarter panel he spent weeks fixing. That and that engine was the death of our old Tempest.

Im not sure if Pontiac were ahead of its time there. Jaguar had been producing the xk 6 for almost 17 years by the time this engine was introduced. The xk was a phenomenal engine. Still is. Twin cam hemi inline six with a 4.125 stroke and rods that are 7.75” long. Still, Thanks for showing us this unicorn engine. Also thanks for the research on it. Many of them scrapped without a second thought.

I say find and rebuild a big block Pontiac V8 (389,455). Put it in the Tempest. But save that OHC6. It can be rebuilt and can be used to power a generator in case of a power outage.

Best lookin mechanic ive seen, she is

Thanks for doing this vid Liv!!!!

that cam cover would make a cool piece of garage art

nice top end pics 👀👀👌👌

That six is a gem of innovative, cost effective engineering that just missed the mark. In a pristine environment their cam oiling solution probably worked great. In the real world of missed oil changes and sludge buildup it became a point of failure. Too bad.

I ran into a problem like that years ago on a 4 cylinder Pontiac Sunbird that somebody did a head gasket and put to much silicone on the valve cover and the silicone covered the oil holes and restricted oil flow to the cam, I noticed all the orange silicone on the head so make sure the oil holes that go to the valve cover are clear, also an old engine just might have low oil pressure.

that is a great engine. Given the sludge that is present in the engine, it is likely that the oil passage to the cam was partially block starving the cam and rockers of oil. An interesting point is that the engine had hydraulic lifters/lash adjusters.

OOOOOPS , That broken bracket might be a little hard to replace ;(

That noise are the cam lobe riders that connect to the hydraulic lifters. You’ll need a cam, cam riders, hydraulic lifters. Good luck finding them. Jay Leno has blog restoration update done in the last 6 months on his channel. He goes over what he had to do on his 4V OHC engine. Basically the same problems as yours.

First time I saw one of these was in 67 in front of our barracks in the army This was one of first uses of timing belts Said would run for 500 tho without trouble Looks like that one may have almost made it

A 4200 straight 6 out of a Trail Blazer would be cool

Poor straight sixes. They never get any respect. Everyone always goes with a V-8. I think it would be way more interesting to build a high performance straight six and see how fast you could get it to go in the quarter mile. In the late sixties early seventies a friend of mine held the NHRA national record for low e.t. in his class runing a straight six in a '65 Chevy Bel Air. All his friends would brag about fast their cars were and then he would take them to his garage and show them the plaque on his wall for his NHRA national record and that would shut everyone up real quick! Cool video.

Had one of those when I was i kid Grampa had a 65 GTO tri-power I am now work at Ford in Dearborn R&E center

My uncle had that very car. I remember It said Sprint, on the fender. 4-speed. Very advanced, for the time.

Hell yes Mr.Holder Can't wait to see on Dyno, turbo charged?

Love you Olivia, real stuff, and so cool.

Now this is just me but instead of sticking the ls in it I'd go through that straight six and overhaul it put a bigger cam and a larger Turbo with a 4l80 transmission and drive that road warrior. ..

Interesting video but you should know that sixes were very common back in the sixties. Muscle cars of any type were fairly rare, maybe one out of every ten or fifteen vehicles, but they are the ones people remember. The best selling muscle car at the time was the GTO and they sold 130,000-ish in their best year. The best selling car was the Impala with 1.4 million sold in '64 so there were more than 10 time as many Impalas as "Goats". Lots of cars back then had OHV sixes and three-on-the-tree manual transmissions bur OHC sixes were very rare in detroit iron. The OHC sixes were considered to be higher performance option compared to the workhorse OHV sixes but did not give as much power as a high-compression small block V8 with a 4bbl. The Sprint powered cars were quicker than the same cars powered by a V8 with a 2bbl.

I remember seeing very few of these engines as a kid, the few I saw were in tempests

Good time to look for a Sprint 6 engine to replace this one. There is a seller in Ga. on ebay that got a 1 bbl of this "Rehol-261".

Back in the late 60s, my friends brother stole a 65 GTO and bought a 65 Tempest that had a bad OHC 6 in it. He put the 389 and 4 speed from the GTO into the Tempest and also all the body trim and interior from the hot GTO to the Tempest after he painted it. He thru all the old Tempest parts into the GTO and pushed it over a cliff into the Clackamas River. He kept the GOAT for a while and then sold it

Do Not throw away that powerglide transmission. the OHC 6 makes a good boat anchor.

That cam design is very similar td Datsun 240-280z inline six and Thay are cams and follower's also

Should pulled the front clip then it would a few things done at one time , all aluminum block is what it needs just wait til you get one to go in it nice O’Reilly‘s auto parts commercial thanks BigAl

What I know for sure Is" She Is Sweet! and she works on cars! RARE" Whoever the boyfriend Is Marry Her Now" You won't find one as Sweet as she Is Ever again! Beautiful!

you have a gem girl the best car ever love it from bedford va

Poor factory camshaft oiling system design did it in. An exterior oil feed line/tube would constantly deliver oil to the camshaft and rocker arms. Maybe the previous owners kept using engine oil designed for catalytic converters. The absence of zinc in the oil may have ruined the cam lobes too. Maybe the oil pump was wearing out also?

The old motors of yesterday need Zinc in the oil . The government had zinc removed if you dont use a zinc supplement you will blow your camshaft.

To awesome girl I'll definitely be following along, and weighting to see that OHC 6 on the turbo booster, right after he does his thing with the Northstar. Just kidding of course, lol.

Pleases save the OHC6-everybody scrapped them for a V-8-they are cool-as is your channel!

One thing I learned a long time ago, if you don't break the cam in correctly ,it will be rounded off after 15 minutes or less.

I had one of those overhead cam sixes I rebuilt it high-compression Pistons Portishead Turbo make 418 horsepower

The gasser stance look for the Pontiac? Take a viewer vote on that might be a good idea. I am not a big fan of the old gasser look but some people love it. Let the viewers decide.

Put C10 2wd truck springs in it....I did this in a GTO of mine car had a nice stance....

Richard Holdener ? cool 👍

They were famous for timing belt breakage

When you glob RTV it blocks passages and that's the results. Just a fingers smear is all you need

Watch Jay Leno. He has a Firebird with that engine and explains it’s weakness and how to fix it.

I had a 67 chevelle 300 post car like that. They are lighter than the Malibu. That rear window is hard to get!

I like one row interceptors....They we're dependable...

How are the cam bushings replaced?

Love vintage Gassers. Tempest has the look of the classic GTO. Go straight front axle, no front bumper, supercharger, scoop or stakes, headers venting out the front wheel wells, tinted window glass. 😎

hay liv put a 301 /4.9 ltr in that nice little tempest

Needs the quadrajet upgrade used on some of the OHV 6s

Every cam is a turbo cam except that one this one went from a stock round lobe cam to a flat lobe cam

Damn why is all good fun ladies taking

I was hoping you would do a tear down of that top end.Pretty interesting how that worked.Or didn't work apparently.Still pretty cool though.

I am so excided for you and seeing you start your project. If you need any help I'm a Certified Mechanic and I will work for Free because I got you and your team back 100%.

Yeah that motor would take a lot of money to rebuild right as much as I'd like to see it stay original V8 would be a lot more fun to drive I wish I could help you out a friend of mine has one of those engines with a 4 Barrel on it but it is buried in a barn in Ohio I agree with the Gasser look I think they look great on those cars anyway whatever you decide to do good luck with it because that's a nice car I've always wanted one myself

I'm telling you look into the4200 vortec boosted there a monster

I just don't understand why they didn't go with a cross flow cylinder head design & stay with the "proven" pushrod valve train (same cylinder head design as a V8 cylinder head just longer for the 2 extra cylinders/combustion chambers) that way the intake manifold would mount on one side & the exhaust manifold on the other side instead of having them both "stacked up" one manifold on top of the other manifold...plus, with the intake ports on one side & the exhaust ports on the other side - advances could be made with diameter openings instead of having both intake & exhaust ports "crowded up" on the same side of the cylinder head 🤔