Engine swap <yawn> and data logger hp

#41

You can use the part from the slave on one end, and after adjusting the length, the plastic end piece from another push rod. You cut the two to adjust the overall length for the clutch. CB

#42

I made a slave rod 10mm oversize and it didn’t change behavior. Since I tested the slave to the extent it busted my bleed fixture, it must be a bad pressure plate. Maybe somehow the crash killed it. That’s ok, I think I have 4 clutches up in the attic.

Once I remove the suspect pressure plate I’ll see if I can’t rig up a test that shoves the thrust bearing into it so I can see what it’s doing. Or not doing.

#43

On Friday Chris Tuttle’s motor swap was complete, not that I helped him and Rich much. That got Chris’s car out of my garage and my car back in.

On Saturday I pulled the transmission for the 5th time and put on the clutch disk and pressure plate that came with New #6. Today I put the transmission back on. For the 5th time. My clutch works now. Sheeze what a pita that was.

I’d have avoided a lot of trouble if I’d recognized that the slave needs to be engaging the fork about 5mm before it gets to it’s 8mm studs.

#44

Congrats. I was hoping we could get the swap done earlier, and I could help you with the transmission. I want to say thanks to Scott and Rich for all the help last week including Rich for the engine swap help and Scott for the hospitality, spare parts, and coming home from work to help me reinstall my hood on Friday so I could get on the road to Sebring.

#45

At last I have good news. I need to do another engine swap. Transmission R/R #5 did the trick. I gave up on my cool low profile clutch that was in Old #6 and reinstalled the original OEM one that came with New #6. It’s heavier, but the darn thing works. I’m not sure what was wrong with the low profile pressure plate, but I’ll try to figure out how to test it in a press or something.

I did some careful compression and leakdown testing tonight on the engine that I installed 2 weeks ago and I’ve decided that there’s something going on with cylinder #6. I’m getting 8-11% leak on all cylinders past the valves, which isn’t great, but #6 has 30% leakage. Unless I can come up with some more ways to test this engine, I’ll be pulling it in the next couple of days and installing the 2nd bottom end that I built at Metric Mechanic 18months ago.

Ok, there is actually some good news. I think I finally figured out how to use my damned leakdown tester. I only “sort of” understood before such that I could get relative #s, but not absolute #'s. Until now. So that was nice.

#46

Scot - They should make a Dos Equis commercial in your honor.

#47

Scott, you did not freshen the head!!! If you have not overheated the bottom end, you need to freshen the head before you change!! CB

#48

I’ll second that. You’d be surprised at how little error on a valve seat it takes to see 30% (or more) leak down. If a head is pretty fresh, tearing it down and lapping the valves can make a big difference and in the process you can tell if a re-grind is needed.

Lapping valves is quite easy to do and it doesn’t take long.

#49

My bust, I wasn’t clear. 30% leaky #6 was, near as I could tell, all cylinder wall leakage not valve leakage. That’s why the engine is coming out.

The bottom end coming out has my only oversize pistons. Later this year I’ll pull the bottem end apart, figure out what is going on with that cylinder and then either fix it or bore out another block to re-use those pistons.

#50

Engine and transmission are now out. Rich Bratton was at the house last night so he helped. It’s very helpful to have a 2nd person when lifting an engine out because the 2nd person can spot all the things that you forgot to disconnect or are wrapped around something. Last night was one of the first times I pulled an engine w/o a screw-up that beat the shit out of something.

Tonight I’ll pull off the manifolds and head. Then I’ll do a drip test of the valves to see how much leakage there is before we lap them.

#51

Last night I did some disassembly on the motor I’d installed only the previous week, did a drip test on the head to check valve seal, and used a bore gauge on the cylinders in the hopes to understand why so much air was getting by #6 piston.

Dry compression
140
140
130
132
137
127
Conclusions. 1, 2 & 5 “might” be ok if engine isn’t turning over that fast. I’d be happier seeing 170psi tho. 4 is not ideal, 3 is worse and 6 is a real problem. 6 seems to be nearing the threshold of no combustion.

Wet compression
145
143
140
143
143
150
Conclusions. 6 might have serious ring leakage, 3 rings pretty bad too, 2 rings no prize. Valve seal on 6 particularly good. Maybe weak rings have made for an easy life for #6’s valves.

Leakdown (where)
8% top
10 top and bottom
6 top
5 top
8 top
30 bottom.
Conclusions. Leakage should be <3%. #6 is having a ring seal crisis. 1, 2 & 5 no prize.

Inverted drip test.
Perfect is no drips past valves. Marginal for racing is 3drips/min.
1 and 3-6 no drips, perfect seal.
Chamber #2, 10 drips/min.
Conclusions. Head seems to be sealing pretty well, except for #2.

Cylinder measurements.
All cylinders nicely round and cylindrical.
Smallest is #3. Using it as a baseline
+1 thou
+6 tenthou
baseline
+8 tenthou
+9 tenthou
+3 tenthou
Conclusion. Nothing here explains significant leakage past #6 rings. That’s pretty irksome. I’d really hoped the bore gauge would help me understand why cylinder #6 leaked.

Overall. Well, nothing here seems to confirm anything. The compression and leakdown tests clearly showed that there was valve leakage at all or almost all chambers, with #6 having a bad leak past the rings. But the drip test did not confirm widespread leakage and cylinder measurements did not find anything problematic with #6.

So what’s a boy to do? Well, drive on and hope for the best, I guess.

This morning I took the head, cam and rocker arm retaining shafts to a machine shop so they could be inspected for crash damage. I want to make sure that everything is straight. My opinion had been that the head did not take much of a hit in the crash. The radiator wrapped around the head and crushed the distributor cap but nothing hard hit the head. But when I disassembled the head I found that the front of the cam apparently took a whack. A chunk of steel was missing adjacent to the cam gear locating pin. The locating pin was only barely being held in place.

When I get the head back Rich Bratton is going to help me lap the valves.

#52

Leakdown is always takes at TDC…lower readings mean nothing as that is not where the piston needs to seal. If the head is not off, you need to recheck each cylinder at TDC!!! Chuck

#53

Head is off and disassembled, no going back.

Leakdown tests were done at exactly TDC. I did each cylinder at least 2x to make sure results were repeatable. #6 I did 4x.

#54

What was leak down at TDC? CB

#55

Leakdown (where)
8% top
10 top and bottom
6 top
5 top
8 top
30 bottom.

The “top” and “bottom” is a reference to where the leakage was, not where the piston was. Sorry for the ambiguity.

#56

Head checked, engine stand built, and the first look at the 2nd MM bottom end.

A pretty common site over the years…#6 with no engine.

Old engine, relatively stripped now, with the transmission in the background.

The machine shop checked out the head, cam and rocker arm shaft retaining rods. All good. Fortunately the guy hustled and I was able to go fetch the disassembled head the same day I’d dropped it off.

I had problems getting my engine stand back from the guy I’d loaned it to so I went to HF and got another one. I assembled the stand and then used the hoist to lift the bare Metric Mechanic block up on to the stand. It’s awful pretty but it sure is a bummer that it doesn’t have oversize pistons. It doesn’t even have new pistons…they’re cleaned up take-offs.

I got a little done with the assembly of the MM motor.

#57

I was out of town for a couple days on vacation. Last night I removed the OEM baffling from an oil pan and installed a left side door. I also put the oil pump, timing belt, water pump and harmonic balancer on the MM bottom end so it’s ready for the oil pan and head.

After fighting all day with the outfit that moved, lost and defaced his household goods, Rich Bratton came out to my house to show me how to “lap” valves.

Rich then took one of my oil pans and an 1/2NPT bung because he’s making a run to our “aluminum welding” machine shop as opposed to our “engine” machine shop. The bung will be for an oil pan mounted temp sensor and I’m not yet confident enough re. my aluminum welding to be comfortable that I’d make a perfect seal. The shop is also going to make some right side oil pan baffles for us and that I can probably weld into place w/o burning holes in the oil pan. Probably.

Last night I tried Harbor Freight “heavy weight” latex gloves for the first time. I’ve gone thru dozens of boxes of their “medium weight” gloves. It will be heavy weight from now on. I went thru 1 glove in 4hrs instead of a pair of gloves every hour. Very nice.

I’m heading back out of town so the head and oil pan won’t go on the bottom end until Monday.

#58

[color=#ff0000]NEVER[/color]miss an opportunity to lap the valves. That is where the HP is made. CB

#59

Ok, this is about done. Recap. It wasn’t until a couple weeks before RA that I had enough data to identify that the engine that came with New #6 wasn’t what I thought it was. Leakdown tests confirmed it. So I grabbed my only block with oversize pistons, mated it with the head from crashed Old #6 and entered clutch hell.

The eve of RA I pulled the transmission for the 4th time trying to beat the problem…and when I put the transmission back on with it’s long clutch shaft, it still didn’t work. The clutch would disengage only a little. Which was actually progress compared to tranny R/R attempts 1-3.

The 5th time I R/R’d the transmission I replaced the pressure plate and the clutch finally worked. But, sadly, that was the day after RA.

Then, for the heck of it, I did some compression and leakdown tests on the engine, now that it finally worked, and to my horror it wasn’t all that healthy. Several valves leaked and 1 cylinder leaked. Sigh.

So I pulled the engine, that had been such a beast to install the week previous, back out of the car. This time tho, I got deeper into the mysteries of the head. With Rich Bratton now in town I got motivated to learn a lot more about top ends. Night after night I tested different rocker arms and cams with a dial gauge to see how much valve lift each combination gave me. That was interesting stuff.

Rich and I also lapped the valves of the head during this period.

Then I put the head on the motor, the motor on the tranny and the whole damned thing into the car. At this point I was starting to run low on time because Jon Stroup was coming to town Saturday morning (tomorrow) to do an engine swap and my car needed to be out of the garage. My engine needed to be entirely in place a day or two in advance so I’d have time to work thru the inevitable goatscrews when the engine failed to start.

But to my great delight and mild surprise, the engine started up this evening and I drove it out of the garage.

I had 3 engines installed in I think 5 weeks. That’s a lot even for me. I’m hoping I can make it a couple months without an engine R/R now. Yes, that would be nice.