cooked 2.8

[SIVAllan]

I thought to file a brief status report on my Series 1 v6 conversion, using a motor of unknown prior history.

After about 4 years of on/off work, I ran out of things to hook up and went for a test drive.

Unfortunately, six miles later the engine dumped 5 qts of oil and oil pressure fluctuated wildly then went to zero.

I got it off the rush hour highway into a parking lot as this happened but believe not in time and the engine was damaged.

I suspect the rear seal.

AAA towed me back and with the car on stands I don't see a leak at idle, but am reluctant to go to higher RPMs.

I wanted to autocross this car at the upcoming United in Norcross, Ga but that "ain't gonna happen."

Sunbeam owners often trailer non-running cars to the Uniteds so I'll consider it, if somehow it's the only Series 1, and if I can borrow a trailer.

A few observations:

The T-5 was confusing to shift. I guess it takes more than six miles to get the hang of it.

The Wilwood clutch slave cylinder may not be the best choice for a Series 1.

The pedals are different, much smaller, and are positioned up high while the clutch catches at the last moment.

It's a hard clutch pedal so the setup translates into starting off with a lurch. Practice might make perfect but it was noteworthy.

The big Series 1 steering wheel is for purists - it will be replaced with an old wood Tiger steering wheel.

The stock temperature gauge went to the right pretty quick so maybe twin small electric fans are worth considering.

Otherwise, the car rocked along pretty good, stock wire wheels and all.

 

[DanR]

Sorry for the troubles .....

Especially after all the good work and time committed to get'n her-on-the-road.

Hoping for a better start and Finish....with my Commodore Blue

DanR

 

[Paul A]

Allan

Sorry to read about the troubles. It is always a thrill when, after so many months of work and the associated expectations, to take the car out for its first ride. I cannot imagine how it must have felt to see that oil pressure gauge go south! Bummer.......

I hope there is no serious damage and that once you locate the source of the leak you can fire the engine and go for a good ride.

 

[Mike Armstrong]

Hi Allan.

The 'using a motor of unknown prior history' part, is the most concerning. I know because I rolled the dice on my V6, perhaps you did too. My 'it used to run fine' engine looked ok (actually looked great after some paint) and began to run fine, but turned out to have multiple cracks in both heads. I should have listened to others that told me to have it inspected and rebuilt right off the bat. Next time.....

Not sure if just a poor rear seal could dump 5 quarts that quickly but it sounds like you'll end up pulling the engine anyway to find out.

As far as the T5 being confusing to shift, if your referring to 3rd gear I, and at least one other member have had difficulty finding that gear consistently and the cure might be an aftermarket shifter.

 

[V6 JOSE]

Hi Allan,

Check to see if your oil pressure lins isn't burned through or broken. I burned a hole in mine (plastic or nylon) and it didn't take long to dump three quarts of oil on the ground.

I doubt that you did any damage, unless you drove it for a couple of miles and the motor started to seize.

José

ps Pull the oil pan and take a gander at the bearings. If they are OK, I'd take the opportunity to install a high volume oil pump. (Melling)

 

[RootesRacer]

I once dumped the better half of an oil pan of oil while out and about.

When I brought it back in I was hard pressed to find the leak as it wouldnt leak a drop running with me watching it.

Turned out a previous oil filter seal had stuck to the block and it had two seals.
When the oil pressure was high enough the pressure would deform the seal on the block side and it would blow oil.
At idle and most other conditions it would not do it.

Go figure.

 

[Alpine66]

My oil pressure line popped when I was driving, what a mess.

replaced that set up with a sender in the block and wire between it and the gauge, no more oil spray.

 

[SIVAllan]

Folks thank you for the analysis - this group constitutes a deep bench of experience that is extremely helpful.

So far as I can tell the initial suspect - the rear seal - is the culprit.

A picture of the leaky rear seal is attached.

No other leaks can be found, even with the engine idling for 15 minutes and me beneath, waiting and watching .

I hope to replace the seal this week to enter the car in the big United car show in nearby Norcross, Ga.

This is a huge event in the Sunbeam community and it will not return to the Atlanta area for many years.

Unfortunately the loss of oil and brief surge of high heat left the little v6 with lowered oil pressure.

Before the seal leaked 5 quarts of oil, the oil pressure was 55 cold and 25-30 hot.

Now it's 30 cold and 25 hot.

So that's a mishap that speeds up the planned overhaul from this winter to October.

For now, 50 weight oil is on the list of things to do for short term help with the oil pressure.

I'd still like to autocross, if the oil pressure stays above 25 or so - would that be a problem ......

 

[RootesRacer]

You need to check deeper why you would lose so much oil out a rear seal.

Its one thing to drip a little due to a leaking seal but to loose 4 qts of oil in minutes takes a huge leak under pressure. The seal should not have been under oil pressure. Perhaps you built up some crankcase pressure and blew out the seal but that should have resulted in moderate not huge oil loss.

 

[SIVAllan]

You need to check deeper why you would lose so much oil out a rear seal.

Its one thing to drip a little due to a leaking seal but to loose 4 qts of oil in minutes takes a huge leak under pressure. The seal should not have been under oil pressure. Perhaps you built up some crankcase pressure and blew out the seal but that should have resulted in moderate not huge oil loss.

Yes, the mystery needs resolution, lest history repeat itself.

The motor allegedly was "rebuilt" by the owner prior to the guy who sold it to me.

Its intended use was a T-bucket hot rod of some type and it had some weird, home-made mounts bolted to it.

It had sat outside for many months beneath a tub, on the ground.

It was very clean and had been painted and that's all the history on this motor - so any and all possibilities are on the table.

One possibility would be a poorly installed rear seal.

Given my limited ability to test, and not too many tools, the best option is probably to tear it down as soon as I can, instead of waiting on the winter.

I have some speed parts for it, including a Jose grind cam and a pair of ported/polished heads with 2.9 valves and hardened seats. So a teardown is definitely going to happen.

But no time for that just now. Replacing the rear seal seems like a good gamble for the less than 200 miles of use that's needed before a rebuild.

 

[SIVAllan]

My buddies and I replaced the rear seal on the 2.8.

The leading theory for catastrophic oil loss was that a bad rear seal caused 5 quarts oil loss in just a few miles of the maiden test drive.

We replaced the oil seal and began test running the engine to see what happens.

Before the incident, the engine idled smooth with 50 pounds of cold engine oil pressure that fell to 25--30 pounds hot oil pressure, using 15/40 oil.

After the incident, the engine now idles smooth with 50 pounds oil pressure at cold idle - using 5 qts of straight 50 weight oil.

But after 20 or 30 seconds of idling at 50 pounds, suddenly the pressure needle dives to 10 or 15 pounds and I shut it off.

I try again after while and - same thing.

What would cause the stock oil pressure gauge to read 50 when cold but after seconds of cold idle - oil gauge suddenly drops like a stone to 10 or 20 pounds. ??

I'm thinking 1) oil pressure gauge has an issue or 2) oil pump has an issue...or 3) engine bearings are worn... ??

Regarding the oil loss culprit, the rear oil seal may have contributed but another suspect now seems more likely.

The home-made fitting hooking the oil pressure gauge's plastic line to the block was not very tight upon return from an oil change, but not leaking.

However we moved it a little to tighten then cranked the engine - only to see a half quart oil loss in seconds - without leaving a trace on the block.

Possibly it wasn't correctly tightened before.

Thanks in advance,

 

[weaselkeeper]

Agree with earlier post that a rear main should not be under pressure...unless there was no other way for crankcase pressure to escape. Valve cover breather or pvc (if installed) usually keeps that from happening. (plugged pcv???). Even at that, it would take constant pressure and supply from the pump to push the much oil out in a short time.

I had a jeep that liked to retain oil filter gaskets. Double gaskets can leak a lot in a hurry.

Is there an oil galley plug that is missing/damaged threads?

Oil pressure. Your post makes me wonder if there a problems with oil pressure relief springs in the oil pump.

Thinks that make you go 'hmmm'.

 

[SIVAllan]

Agree with earlier post that a rear main should not be under pressure...unless there was no other way for crankcase pressure to escape. Valve cover breather or pvc (if installed) usually keeps that from happening. (plugged pcv???). Even at that, it would take constant pressure and supply from the pump to push the much oil out in a short time.

I had a jeep that liked to retain oil filter gaskets. Double gaskets can leak a lot in a hurry.

Is there an oil galley plug that is missing/damaged threads?

Oil pressure. Your post makes me wonder if there a problems with oil pressure relief springs in the oil pump.

Thinks that make you go 'hmmm'.

Thank you and everyone for helpful replies to this and other issues that have arisen as the Series I was converted to v6.

We are pulling the engine and putting it into inventory due to too many issues.

Some time ago, I bought a dissembled 2.8l v6 engine and it now steps up as a replacement.

A few pieces are missing such as oil pump and bolts to attach it, camshaft thrust plate and bolts to attach it, and oil pan plus bolts to fasten the oil pan.

ARP rod bolts will be obtained from Summit but I am unsure about others, including head bolts.

We also will try to determine if balancing is worth the expense for a mildly warmed up street engine.

 

[Mike Armstrong]

Good call Allan.

If anyone asks me about what's next for their newly purchased old 2.8, I'm going to suggest getting it overhauled right off the bat. A tear down will reveal what you've got 'before' you start spending money, spraying paint or doing a quick install (not saying you did). I didn't listen and after a few new gaskets, parts and paint I excitedly went through the trouble of installing my mystery (no verfyable history) 2.8 only to be dissapointed.

That's good that the other engine is already disassembled. Great opportunity to check everything out (have those heads magna-fluxed!).

There's something seriously wrong with an engine that dumps oil like that and it's even more scary when it's not obvious where it's spewing from. You made the right decision.

 

[V6 JOSE]

Hi Allan,

Balancing is always good, even if it is a stock engine, because it lowers vibration (although the little V6 , being a 60 degree design, is naturally balanced) and helps it last longer, because it isn't fighting itself.

Thank you and everyone for helpful replies to this and other issues that have arisen as the Series I was converted to v6.

We are pulling the engine and putting it into inventory due to too many issues.

Some time ago, I bought a dissembled 2.8l v6 engine and it now steps up as a replacement.

A few pieces are missing such as oil pump and bolts to attach it, camshaft thrust plate and bolts to attach it, and oil pan plus bolts to fasten the oil pan.

ARP rod bolts will be obtained from Summit but I am unsure about others, including head bolts.

We also will try to determine if balancing is worth the expense for a mildly warmed up street engine.

 

[DanR]

Balancing Bob Weights....

Allan, A few years ago I was pressed to find a Machine Shop to "Balance" my engines (2.8 V6's) Located a shop in Charleston, SC. The owner turned out to be a fellow drag racer of mine from the early to late '60's.

He does great work. The distance from me is about 200 miles.

I thought it would be a great idea if I had my own, so, after a couple tries, I located a set of the very hard to fine "BOB WEIGHTS" for the V6 and made the purchase. Had my machine shop balance another of my engines.

Greenwood Auto and Machine has them for doing Customer request for balancing the V6 engines now!

Contat me if interested in getting yours balanced. Cost is less than $200.00

DanR

 

[SIVAllan]

Allan, A few years ago I was pressed to find a Machine Shop to "Balance" my engines (2.8 V6's) Located a shop in Charleston, SC. The owner turned out to be a fellow drag racer of mine from the early to late '60's.

He does great work. The distance from me is about 200 miles.

I thought it would be a great idea if I had my own, so, after a couple tries, I located a set of the very hard to fine "BOB WEIGHTS" for the V6 and made the purchase. Had my machine shop balance another of my engines.

Greenwood Auto and Machine has them for doing Customer request for balancing the V6 engines now!

Contat me if interested in getting yours balanced. Cost is less than $200.00

DanR

Thx Dan,

At that price I'm definitely interested. I can drive up your way most any time.

What would I need to bring?

Would your machine shop also assemble my short block?

I'm still assembling a few bits and pieces but believe I have them all.

The block looks good. I can't feel any lip at the top of the cylinders and they measure out to stock size along with the pistons.

BTW AutoZone sent me a Chevy oil pan in a box with a Ford parts number. How great is that.