Mighty Engine #7 swap thread

#1

Sunday night after I got home from CMP I did a compression test on sad #6. 5 of 6 cylinders were so low on compression that they would not have fired. Then I did a leakdown to see where the leakage was. Rings.

I don’t have a theory for how I messed up rings in 5 of 6 cylinders. The oil pressure adventures that #6 went thru should not have affected them. Rings don’t lubricate like bearings do where uninterrupted flow is critical. Rings lubricate like the cam does…the anti-wear chemistry in the oil’s additive package. In most cases this means ZDDP, largely lacking in modern oils. Brief interruptions in the oil supply should be no big deal.

Driving on, I disconnected and/or removed everything except for the transmission bolts. I removed the intake manifold,the starter which is always fun and the exhaust manifold downtubes.

One of the manifold downtube nuts wouldn’t come off for money or love. It was requiring a ferocious amount of torque and I had almost no room to move the wrench. It was really a bastard. Finally I got under the car with a breaker bar and 18" of extensions and was able to get a bit more leverage on it. That’s when the exhaust manifold to downtube stud snapped. Man, that bolt really didn’t want to come off.

But I’ve a helova lot of spares now so there’s 4 exhaust manifolds in my attic ready to serve.

I knocked off around 1AM.

Monday morning I confirmed the status of mighty #7 with Chris Sneed of Sneed Speedshop, and coordinated for it to be shipped from NC to Savannah. If you want to ship anything big anywhere, I’ve got the outfit that will do it. Cheap and efficient.

I’m grateful to Chris for squaring me away on this. I encourage everyone to go to his shop. Give your money to folks that give to the series.

Monday night I spent a hard working hour ferrying 50lb engine hoist parts from the attic down to the garage, and then assembling the hoist. It took 7 trips to the attic.

After the kids went to bed I decided I’d try to get the transmission bolts removed. I’d thought this was a 2 person job. One person working above to place the Torx socket and the other working below with 24" of socket extensions and Ujoints. But I thought I’d see if I could do it myself.

It took some determination, but ultimately I prevailed and got those hard-to-get-to tranny to motor bolts out.

And I knocked off about 1AM again.

Tonight I pulled the motor out. One of the clutch bolts stripped so I had to drill the damned thing and attack it with an easy out. Then I hit the first flywheel bolt with the impact wrench and I had no air pressure.

My damned air compressor had died. I think that it’s still under warranty so I’ll take it back to Harbor Freight tomorrow.

Then I took the flywheel bolts off the hard way and I’m pretty much ready for the arrival of mighty #7 on Friday.

The plan is to do a leakdown on #7 when it arrives and decide whether or not my good head needs to go on. Then I do the logical “prior to install” tasks Friday night.

If all goes well, Saturday night the neighborhood will hear the thunderous roar of mighty #7.

Misc…

I found an inexpensive source for threaded caps to block off the steering block. I bought a couple extra. $10 and they are yours.

For now I’m not going to put the Accusump back on. I’ve not yet decided how I want the new, simplified, system to work.

I’ve not yet decided on whether or not to install an OEM oil cooler. I’m leaning towards doing it tho. It’s coming from Greg Moberg.

Chuck Taylor squared me away and shipped a crankscraper to me quickly. It arrived today. I swear to god I will never turn left without a scraper again.

I’m going to put an oil temp sensor in the oil pan. Lots of sensors are good, but by putting the temp sensor in the oil pan I don’t add complexity to the plumbing. My old system required two additional plumbing fittings to add the temp sensor.

My birthday is coming up. It would really be a nice gesture if everyone got together and bought my ass a lift. Man how I want a lift. The wife will be pissed, but I’ve got to get one.

The new '06 Ford F150 averaged almost 14mpg towing to/from CMP. That’s about a 3rd better then the '99 Dodge Ram POS. Very nice.

And there we are.

#2

Scott, a good friend of mine just lost his wife. Let me know if your wife would like to meet him. :wink:

#3

That’s very impressive mileage from the F150 while towing. I really hope this motor works out for you.

#4

Good Luck!!!

#5

good luck!

#6

good luck! here’s hoping that 7’s your lucky number!

#7

Gasman wrote:

You can’t help it can you?

Scott, everything shipped you’ll have it Thursday!!

#8

So thats about 7 engines in around 14-16 months, which means This engine has a life expectancy of 2-3 months??

#9

Gasman wrote:

Good one. It got a chuckle out of my wife too.

Brendan…Ya just gotta think positive. Besides, all this motor really has to do is last until Chuck Baader finishes the rebuild of #5. 3rd weekend of June I’m taking the car to his place to spend the weekend swapping motors. It will be a treat to hang out with a master.

#6 had a hard life, with all the oil starvation problems. It’s still odd that the rings were the things that failed but some mysteries never do get figured out. It was a serious mistake to put #6 in without a scraper, but since there are other folks running without a scraper for years, I didn’t see the harm in a couple months with no scraper.

Who could have guessed that the combo of no scraper and more elaborate plumbing system would have caused serious problems? I’ve heard no plausible theory that explains how the plumbing could be entirely evacuated of oil such that the pump would have to move a couple quarts in order to completely recharge the system. And I’ve heard no theory about why the car has to sit for 5-10min before starting the car results in oil pressure.

When problems don’t make sense, they aren’t predictable. But learning can still occur. Thanks to hapless #6, the whole community now has some ideas to be wary of. And if I didn’t have something to work on at home, I’d just be drinking too much or surfing the web for porn.

#10

Ranger,

Here is a theory.

With all the extra plumbing and the sump, is it possible that some air is getting trapped in the system somewhere when the system goes dry? This blockage may be stubborn enough to resist the pressure of the oil pump?

The system will only recover after the car had a time to cool down and burps the trapped air?

Just thinking out aloud.

#11

I dunno. I can’t picture a blockage of trapped air resisting oil movement. And oil shouldn’t be able to drain backwards thru the pump, at least not much oil because of the backwash valve in the oil filter.

But if our crank bearings created a gentle suction on the oil line, kind of along the lines of “capillary action”, I could imagine that evacuating the entire oiling system. And that would require the pump to recharge perhaps 3qts of oil filter, oil cooler and plumbing volume. But I pulled that idea entirely out of my butt and I’ve no idea if it really occurs. And it also doesn’t explain the need to sit for 5-10min before I could start the car and get oil pressure.

#12

Good luck Scott… it’s been nice to meet you at a few races this year. It will be even better to race with you one of these days!

Sounds like a real nightmare.

#13

Ranger wrote:

[quote]Gasman wrote:

Good one. It got a chuckle out of my wife too.[/quote] Your best yet, Gasman.:laugh:

[quote]… all this motor really has to do is last until Chuck Baader finishes the rebuild of #5. 3rd weekend of June I’m taking the car… [/quote] A motor swap to avoid 6 weeks of down time? I’d park that damn thing and find something else to do in the meantime.

[quote]And if I didn’t have something to work on at home, I’d just be drinking too much or surfing the web for porn.[/quote] I think we just figure out that “something else.” :woohoo:

#14

What kills rings?? Heat? Or maybe running the engine hard when it is not warmed up?? Did you have too much oil cooling??

Al

#15

i recall another engineer named scott who said “the more they overthink the plumbing, the easier it is to stop up the drain.”

#16

FARTBREF wrote:

[quote]What kills rings?? Heat? Or maybe running the engine hard when it is not warmed up?? Did you have too much oil cooling??

Al[/quote]

I dunno. I’m far from an engine specialist, I’m just trying to learn like everyone else.

Recall that engine #4 failed at RA last Dec because the coolant hose failed. The head was repaired the engine was rechristined “Engine #5”. Which promptly suffered ring failure. The theory was that the rings failed because of the overheat.

That doesn’t mean I understand it tho. The rings should have been able to handle far more heat then the aluminum pistons. Engine #4 had no issues with intermittant oiling. The combo of scraper and Accusump worked fine and I have plenty of data to prove it.

Isn’t it odd that Engine #6 also experienced a surprise ring failure? Two different causes of the same problem?

God how I hate not understanding. It just eats at me.

Jason, re. “overthinking”. I’d argue that there’s no such thing. A person either understands or they don’t.