oil pressure LOST, and then 24 hours later BACK

[Jerry Clayton]

Pete---I don't want to be an alarmist here but a few things to look for as you take it apart--

That main support may actually be distortong the bottom of the block---

The block could be split from the camshaft bore to the main bore along the oil passage hole---

If this is a 289, you might want to seriously look at going to a Dart SHP 4 bolt block at 4.125 bore---

[Pete Munroe]

Jerry..aka: "Alarmist at Large"

Man, you know how to take the glow off a Saturday morning... Block SPLIT...? rather hear "stock-split"...THAT I could deal with..will look for everything as this unfolds.

65' 289 with the 5? or 6? bolt bellhousing set up, not the earlier one...had heard it was stronger than some series of the 302's (maybe the early 80's roller blocks). Anyway, I doubt my engine was 425 on a good day...most of you guys are running a LOT more power than I am.

The Dart block, especially with the 4.125 bore is a great idea, but looking is about all that is in the budget right now...ok...in aluminum...hmmmmm

Good point on the lower end support introducing distortion. The supports' mass isn't enormous, but if they can increase stiffness, they could induce distortion. Seems if a line bore/hone is done with the main caps torques in place, you would add the girdle at that time as well...like a block plate for boring cylinders.

Have been comparing notes with David G on oil pans...Canton and, now, the AVIAD have the "oil-pick trap door assembly" mounted on the diagonal, not straight ahead front to rear. Anyway, David G, and others are running the diagonal setup without significant oil pressure problems for some time.

Speaking with John at AVIAD yesterday he alluded the diagonal setup, which they do now use, is better. He said removal of the scrapper like I did is probably not of great consequence anyway, although I will replace the scrapper. My AVIAD pan was sourced about 2001 and has the original fore/aft trap door assembly.

Questions for today...if the #2 main CAP has turned blue on the edges, does this mean that a line hone/bore is necessary? Of do you just measure and see where are the journals end up?

Will be taking things slowly here, hope to have the engine out next week and start the complete tear down, measuring and hoping most stuff.

Thanks again...will be looking for ideas as I plan the rebuild, so stay tuned.

Pete

[DAVID GAGNARD]

Pete:

65,289 block should be 6 bolt like the later models......from 65 year model to the end of the production line of the 302/351-W,all were "standard" 6 bolt......the 289 production for 1963/64 models were the 5 bolt model....the bellhousings are not interchangeable....

I would have a machine shop check the block and #2 journal cap, slight blueing means it got hot,how much, anyone's guess.....

The 302/351-W block production used the same casting till the 1975 year model,at that point the casting was changed up some,mostly in the bottom end and the blocks were a tad lighter...I would guess most any 302 block made can withstand 400 or so hp.......
My race engine was a 1969 model standard production block with unkown amount of mileage on it when I got it junkyard,served me well for 7 racing seasons,turning 7,000 rpms,engine made 472hp...blew the engine,my fault, nothing to do with the block,actually the block could have been re-used with 2 sleeves,but since I had a couple of extra blocks on hand, I junked it and built another engine on another block....

David

[Pete Munroe]

David,

This block is the 6 bolt 289.

As I get into this process, hoping the pistons (Ross forged) and cylinders reusable with a very light hone for new rings. As a 347" stroker there could be more side wear I have read. The pistons were supposed to have a raised pin to help minimize the angularity. Has never used much oil to speak of.

The block was already bored to 0.040...had heard that is about the limit for the 289 block in a high performance app. How thick the walls are is unknown although it never had a tendency to overheat.

Was going through the MAHLE/Clevite catalogue of bearings (mine are the Clevite 77 series). Looking at the bearing wear patterns library I see a little bit of every problem on every different bearing...

Trying not to worry about much, but at least have an idea of what to go to next if the any of the major stuff is unusable, keeping in mind its going on the track.

Pete

[DAVID GAGNARD]

Pete:

I'm betting your block is o-k, light hone on the bores should clean things up.....if anything to worry about,it would be the crank.....may or may not be able to turn the main journals, just depends on how deep the scratches in them are.....if it is not useable, another crankshaft is not that expensive.....
I'd change the oil pump and you should be able to re-use everything else....
The tear down will tell the story.......

David

[Jerry Clayton]

David---302 and 351 had different deck heights and main bore size

[RICK LAKE]

Pete Munroe Pete think Jerry is trying to save you another failure to start with and if you are going to race alot, the aftermarket block is stronger and better oil system is the way to go IF the pockets will allow it. Getting the motor out and have a machine shop go throught it is next. If none of the mains are spun a sonic check of the block and boring the block .004" and buying custom pistons that are .045" over size. This give you 1-2 more builds of this block. Then you have a .060" over if the block is not cracked.
Can you get oversized crankshaft bearings if the block saddles need to be bored? Is the crank OK?? How much material to clean it up? The whole bottom end will need to be rebalanced again with flywheel and dampener which brings me to another point of endurance racing, getting a custom balance with ATI for high rpm driving. The more the harmonics can be reduced in the motor the better and longer it will last on the track. This is not cheap, last motor I worked with was about $1K. Motor was smoother after this was done.
Have you looked in local junk yards, E-bay or craigs list for another iron block? It might be better to look for another block and save this one for street driving. I don't know how many years of hard abuse this block has giving you but they all have their life spans and like cats have 9 lives. I have seen major damage to cars with rebuilt motors that have been done a couple of times. Trying to save money may cost in the long run.
I think you have hit the limit of what you have in the car at this time. Custom oil pans MAY help, scrappers are not going to hurt anything and only help oil to get back into the oil pan. Dry sump if you keep racing is going to be needed. An accusump is a fix but again how long will this work. I didn't pull bottom bearing on motor yet and know my car pulls about 1 "G" and on long turn know that the accusump is pushing oil into the motor. I also have rolled off the throttle at this point to allow oil to return to the pan faster. You would think that 12 quarts of oil would be more than enough to keep any motor alive on the track, it's questionable. Compare rebuild against replace for block and bottom end machine work and parts. Good luck Rick L. Ps there is a 5 bolt 289 block on e-bay for $200.00 stock bore with lite rust in NJ about 1/2 hour from my house and Dyno-flo has short blocks for $1,900.00 at .030" over seasoned in NV also on e-bay. some thing to check. $500.00 with shipping? just a thought.

[Gaz64]

Pete,

I would run a pickup with a larger surface area screen, finer mesh, domed towards the pan.

Hope you can get this back together with little fuss.

I would also place magnets near the valley drains and within the cylinder heads to catch valve train parts if they fail.

[DAVID GAGNARD]

Originally Posted by Jerry Clayton

David---302 and 351 had different deck heights and main bore size

Yes,well aware of that,my point was the same casting was used on each block until 1975...

David

[vector1]

rick lake has good advice, but i wouldn't bore the block anymore. i had a wall blow out on a .060 over block and it is known not to bore the production blocks this amount although a sonic test may tell otherwise, so you plays your games and you takes your chances. definitely fix your oiling problems.

i would look into a shortblock.

p.s. when a cylinder wall blows out you pretty much through the short block away, everything is trashed.

[madmaxx]

Miata spec racing would be a lot cheaper

[DAVID GAGNARD]

Originally Posted by madmaxx

Miata spec racing would be a lot cheaper

Shifter karts are faster and cheaper than Miatas

Yes on both counts, but still not a Cobra!!!!!!!!!!!!!!

David

[Pete Munroe]

Guys,

Stopped dis-assembly yesterday to make a serious push to de-clutter the garage. Two work benches, have not seen daylight in years. So much flippin' junk. Buying tools I already have but can't find...

At this point lots of plastic sandwich bags, labels and parts being organized in boxes to keep the process sane.

Engine may come out later this week. When the block goes off for work I will do a final garage scrub before putting it back together.

If the block is useable with at most a hone it will get another go. Reluctant to bore over where it is now, 0.040. At 0.045 special pistons are needed and expensive. May as well put the extra cost into a new block. (friend spent LOTS of money on custom piston size for his 427-351 stroker rebuild)

Jerry's vote for a DART block, in the long run you know what you are starting with. Lots of trade offs.

Point on balancing well taken...this crank is (was) internally balanced. The aluminum flywheel, etc is also at "0". The main bearing journal #2 is the wild card as to how much to cut...hate to go 0.020. We shall see.

The wet sump thing would be great but it seems a more modern pan, with the door assembly on the diagonal works for a lot folks. Car is mainly street driven, and the price is not doable.

Crazy how even moderate track use beats up an engine, or exposed flaws in set-ups. I am just NOT that aggressive a driver, open track only, not "racing" like a lot you guys. Seems the engines suffer just the same.

Will try to get the engine out and apart by next weekend. Parts in clear sight, bores measured, etc. We shall see how far this has to go.

thanks again, Pete

[Jerry Clayton]

Shifter karts are faster and cheaper than Miatas

[madmaxx]

Keep cobra for street driving and Miata or shifter car for track work, others are much safer at speed to boot. As far as your engine call blykins or kc, see what they can do for you, in the long run may be a lot cheaper. I have no doubt you can assemble, but when comes tp balancing and matching components, they know what works with piece of mind, easier to save money elsewhere

[Rick Parker]

Is your pan like this?

[Rick Parker]

Is your pan like this:

[Pete Munroe]

Rick,

That looks like it...don't think I posted photos...

Mine is the AVIAD original design 60's type Cobra pan...I ordered it from them directly about ~2000.

According to John at AVIAD the pickup box with the four swinging doors is now mounted on the DIAGONAL and NOT fore/aft like the original. He also said that new design does work better.

David G has a Canton roadrace pan with the with the diagonal orientation on the pickup box and say no oil pressure problems in vintage racing for several years at 6 different tracks...

Would think at least one of those tracks has a LONG right hand sweeper like turn 2 at Willowsprings...another long right hand sweeper at Buttonwillow, just after the "Magic Mountain" hillock.

After the engine is sorted out, it looks like I will be springing for the newer pan configuration with the diagonal mounted pickup box.

Pete

[DAVID GAGNARD]

Pete:
if you can post a few pictures of the inside of your pan and I'll post some of mine for comparison.......there's a big difference and I think that is the root of your problem........

David

[Pete Munroe]

David G and I have been comparing our experience with oil pans. This is my AVIAD Cobra pan. This is the original configuration from the 60's in which the oil-pump 4-swinging door assembly is oriented fore-aft.



This pan was sourced new from AVIAD about 2000. The new version has the pick-up box mounted on the DIAGONAL. According to AVIAD and David's experience with his Canton the diagonal setup is more effective at retaining oil-pressure.

Pete