[SPGlass]

Just a little Lamborghini porn for everyone. More to come soon!

 

[SPGlass]

Just a note for anyone doing this in the future. The cylinder liners are not pressed in. There is a couple thousands clearance. They may get a bit stuck over time but the machine shop that removed them heated the block to 200 degrees and they slid out by hand. I had originally sent it to Millenium Technologies who had it for 2 months until they told me that the couldn't even get the liners out. The new ones slide right in if you get them straight. I expect that they will be a bit tighter with the o-ring on them but should still go in by hand.

Also, these are just iron sleeves instead of the nickel silicon carbide plating that they originally had. I heard from many sources that this is know to fail and should not be used. So I would suggest that anyone getting new sleeves get them from L.A. Sleeve or elsewhere that will make them from Moly 2000 iron.

 

[SPGlass]

The heads turned out phenomenal. All new guides, valves straightened and checked for taper, valve seats ground, valve lash adjusted, valve springs specs checked, cleaned, and heads checked for straightness.

 

[Sledge4.2]

Awesome.

 

[ARANCIOBULL]

Very nice

 

[DiabloClyde]

Thank you for taking the time to post these pics and your experiences.

 

[SPGlass]

I've been having things pop up left and right lately so progress has been slow. Now that I think I have everything lined up to start assembly the bottom end I think I will start filming the assembly because I think it is a very interesting process and haven't had much luck finding any video footage of anyone doing this aside from a quick 1-2 min time-lapse.

Today the machine shop should be finishing reaming the small end bearings. I sent the injectors out to ProFlow Performance Fuel Injector Technologies for servicing. They did a full servicing on them and found them to be VERY dirty! He said he cleaned them 9 times. 3 times more than normal! The flow improved between 6-14%.

I also am treating my radiator with radiator flush to get them as clean as possible. I hooked up a pump to flow the solution through each radiator for a couple of hours each. I ran it in both directions on each one. I got a lot of sediment out but can't be certain it was not from the pump. The flow did improve noticeably on the first one which was noticeably less than the other one before I started. After that I ran cold water through to get the radiator cold. Then I emptied it and ran hot water through and emptied it again. I then quickly check the surface temps with an laser temp gun to make sure there were no abnormal cold spots that would point toward a blockage. It all seemed very gradual from the inlet to the outlet getting cooler along the way in a U shape.

 

[leslie_choo]

Could someone post a pic of the center temp sensor connector? Mine is not original and I want to replace it.

Does it look like this? View attachment 301623

Seth

I noticed I have one extra connector near the temp sensor thats is not in used . Since you are working on this can you pls check if you have this extra connector in your car too ? I saw another car has the same unused connector too . I hope I didn’t miss out connecting anything . Thanks

My car

Not my car

 

[SPGlass]

Hi Leslie. Yes, my car has that too. I'm not sure what it is for. Does anyone know?

 

[Sledge4.2]

Both my diablos had that stranded wire, no idea where it goes

 

[CCIE]

Very Interesting....... On my 91 its connected...... Lesliy, SP and Deno... Please post full size image so I can make sure its the same cable.

 

[SPGlass]

My car has that one too. I don't recall what it goes to but the one in question only comes out of the main harness about 3". It is even shorter than the one that goes to the temp sender.

 

[SPGlass]

I'm making some more progress with the motor. I have installed the main and rod bearings and checked all oil clearances. All checked out great. I have installed the cylinder liners. The machine shop that has done the work on the engine suggested that I put teflon paste around the top of the liners to seal them as they are not originally sealed at the top, only the bottom. After doing this, I found that the protrusion of the liners out of the block measured .18mm. The tolerance is .04 - .09mm. I found that the teflon paste was keeping them from seating in the block. It was not much fun pulling them back out as the teflon had started to set up but I got them out and cleaned up and set back in without the teflon. The protrusion clearances are now spot on.

 

[Sledge4.2]

Did the liners just slide in at room temp?

 

[SPGlass]

Yes, the liners slide in at room temp. They are not pressed in. They are very tight tolerances so they only go in if they are perfectly straight. There is an o-ring at the bottom of the liners that seals them which you need to put a little silicone on for lubrication going in. The tightening of the heads against the protruding liners is what keeps them firmly in place.

 

[SPGlass]

I've got the crankshaft and all piston/rod assemblies in now. This was the most fun part of the project yet. Putting one piston in after another really gave me a sense of what a monster this engine is. So many steps in this rebuild have made me ever more passionate about Diablos. Turning the crankshaft over once all of the pistons were in was a surreal experience. Partly because it was the result of a huge amount of work but also what an incredible functional work of art every part is and seeing all of the pieces moving in unison. Just incredible! I can only imagine the feeling that I will get when I start the car for the first time.

I am now just awaiting the Loctite 578 that I ordered to get the crank girdle on. That is the final part of the bottom end.

 

[AngelOfMurci]

I've got the crankshaft and all piston/rod assemblies in now. This was the most fun part of the project yet. Putting one piston in after another really gave me a sense of what a monster this engine is. So many steps in this rebuild have made me ever more passionate about Diablos. Turning the crankshaft over once all of the pistons were in was a surreal experience. Partly because it was the result of a huge amount of work but also what an incredible functional work of art every part is and seeing all of the pieces moving in unison. Just incredible! I can only imagine the feeling that I will get when I start the car for the first time.

I am now just awaiting the Loctite 578 that I ordered to get the crank girdle on. That is the final part of the bottom end.
View attachment 313625
View attachment 313626
View attachment 313627

Not too sure if you mentioned it before, but what initially caused you to do a rebuild? Also, how many miles were on the car? Thanks

 

[SPGlass]

Not too sure if you mentioned it before, but what initially caused you to do a rebuild? Also, how many miles were on the car? Thanks

I did but thats ok, it was almost a year ago. The car has about 60K miles. While doing an oil change in 2020 I cut the filter open and found metal shavings. I then did a compression test which was low on all cylinders and leak down numbers were high on all particularly on one. I am not certain what the initial cause of the issue was but there was a lot of debris in the oil pan, all of the bushing were in bad shape including the trust washers that were so bad that the crank was starting the rub on the block which I'm sure only contributed to the issue. I suspect that the issue started before I got the car. The first time I did an engine out I found a bolt in the oil pan that had sheared off from the timing chain guide. As far as I know I got all of the debris from that cleaned out during that engine out but I only did top end work so I did not disassemble the bottom end or clean all of the oil passages. So the oil passages may have been plugged or the trust washers worn already. What is odd is that I never had low oil pressure.

Luckily, most of the was contained to the bearings and oil pump. The crank journals and camshafts looked much worse before they were cleaned up. This makes me wonder if the material that was in the oil was a much softer material like aluminum and or bearing material. With all of the cleaning that I have done before and during assembly of the bottom end, I am confident that the internals are cleaner than when it left the factory. Having gone through the entire engine I am sure whatever the initial cause was has been corrected so I expect to get a lot more life out of it.

 

[SPGlass]

One modification I did is to the oil restrictors that go between the heads and block. The Diablo suffers from a couple of issues that cause damage to the cams. One is that the there can be a lack of oil to the cams. I decided to open the restrictors up form 2mm to 2.4mm. I tried to be very conservative with this since I don't want to open them up so much that it reduces oil pressure. I plan to prime the engine with oil before installing it so I will be able to check the flow then.

 

[Sledge4.2]

Great work Seth, really impressive, and just imagine the feeling the first time you really put the hammer down on that beast.