Here's a pic of me pulling the engine out of my 612 yesterday!

Thanks guys.... my machinist is (again) going through the head. He concedes the two intake valves show slight bend (but was able to machine this out). I am sending him new valves anyway.

It is strange because the other five cylinders definitely showed some leakage through the valves on the leakdown (as evidenced by blowing off tape applied to the intake and exhaust ports). But when I removed the head, and sprayed brake cleaner into the ports, the valves showed no leakage. Obviously the brake cleaner isn't applying a lot of pressure, but still. Also, my compression check prior to the one cylinder of bent valves showed 190 PSi compression on these same cylinders and valves.

My machinist says the valve seats wear in and provide a better seal over time. I (instead) have requested the "good seal" NOW (via lapping the valves) so I can stop screwing around with this crap!

So, weekend after next will be my next opportunity to put on the head (again). Will then take it from there!

 

Alright guys, I am back at it!

I got the head back last week and the #6 cylinder now has all four new valves. Rest were also re-inspected and lapped. I installed the head (no cams yet, just bolted down with gasket). Did leakdown. Voila! It is a GO!

So, will be back to the shop today to build up the timing system. Will be VERY careful this time to not rotate a cam into the valves and risk bending them (when tightening the cam wheels). My approach is going to be to lower the pistons an inch below TDC on all cylinders on the right hand bank. Then lay in cams and get them into the right position. Then bring the pistons up into proper position, then lay on belt and tension, then lower pistons again below TDC, then apply final cam sprocket torque with the belt in place and pistons down out of the way!

Any other thoughts? I hope to start her again before Jan 5th.

Merry Christmas and Happy Holidays to all.

- Jason

 

Thanks Taz.

I got the cams in and all the timing and tensioning set today! I used the exact procedure I outlined and it went very smoothly.

I think (hope) it is all downhill from here. Valve covers, plugs, coil packs, exhaust manifolds, upper plenum and "start"!

I may choose to do a full compression on the RHS head I just installed just to make sure before going any further.

Got lazy and didn't take pics today but the proof will be in the next start video!

 

Merry Christmas!

I think I am going crazy. Perhaps I have more to learn...

I installed the head (again) with no cams in (so valves all shut). Then did a leakdown. All was good (way within the "green range" on my tester.

Then I timed the engine to the procedure I noted above. There is absolutely no way any valve contacted a piston. Then did a leakdown test and each cylinder on the RHS fails.

What is going on here? Do I need to run the engine in to seat the valves? Or do my tappets need to be run to get to the proper length? Could they be extended too far right now and keeping the valves open??

I may do compression test next. Or measure between cam lobes and tappets to ensure I have a "gap" when the cylinder is at TDC compression stroke. Last resort is pulling cams and testing the leakdown again with the cams out (again).

Any thoughts? I need to talk to my machinist again but the drivers side is perfect and that head was done by the same guy (and has seen 30 minutes of running in). Is this guy right about having to run in the valves and tappets?

 

Sorry to get defensive but I am not "over my head". I've made 3 mistakes in 30 years of working on cars. I am just honest enough to admit to this group I made one of those mistakes on this car when I over-rotated the cam into the #6 piston and bent the valves on that cylinder.

I've done dozens of rebuilds and repaired hundreds of cars. No one knows everything but I know a lot. I come to others for ideas on issues that don't make sense. This leakdown issue is one of those things... So, that being said, let's get back to the topic at hand.

Again, I had the four valves on #6 replaced and the rest of the head re-checked. Before installing the head, I sprayed brake cleaner in all the ports and checked for any leakage. All nicely sealed.

I then installed the head (with #1 piston backed down from TDC by about and inch which means #6 down from TDC about an inch too). I leakdown tested the head on the motor prior to putting in the cams. Every cylinder was great. I then installed the cams as close to the "marks" as you can get them when you tighten them down, rotated them slightly to then align the marks, then rotated the motor forward the 30 degrees to bring #1 piston at TDC, put on the belt and pulleys, tensioned it, and was done with timing. Rotated the motor a couple times and then checked leakdown at each cylinder. Now the values are bad. So, since I know I didn't contact any valves in this procedure, I have one of a finiste number of things going on:

(1) the valves require being run in to fully "polish" the seats and give me a strong seal. And though they sealed on vacuum test for the machinist and on bench for me with brake fluid, etc., they were opened a few times while rotating the motor after timing it this last time and aren't quite sealing perfectly until being "run in".

(2) my machinist sucks and screwed up the valve job. However, this guy has been doing this kind of work for 40 years and also did the driver's side head which is holding great pressure on leakdown (though it was run-in for 30 minutes when I initially started and ran the car with the one bad cylinder). So whatever approach he used on the drivers head, he would have used on the passenger head.

(3) the tappets are elongated and need to be "run in" to get to the proper length and dimension and are "over-extended" and holding the valves open slightly.

BTW, the valve cover is still off the passenger side head so I have perfect cam visibility. The cams were installed in the proper locations. Leakdown loss is definitely past the valves and (and typical piston ring losses).

Proposed course of action:

(1) do a compression check. I will need to hook up the oil cooler so oil doesn't go everywhere, but I could run this test and see what it proposes. Plus it make cycle the tappets and valves adequately to get them to seat. I plan to do this with the valve cover still off (or lightly placed with no gasket. Then perform another leakdown test.

(2) bring each cylinder to TDC compression stroke and spray brake cleaner into the intakes and see if it holds. If so, move forward. If not, remove cams and see if the valves then seat. If they do, I have a cam or tappet issue.

Some more context: I've read that tappets can be over extended until they get run in. This confused me a bit but the above tests can isolate. I know my machinist (like most) doesn't lap the valves after the valve job. He says you need to run them in. Many I have talked to have said this makes no sense. I've read conflicting reports. I've also had this guy do dozens of valve jobs for me on other cars and had no problems. There is nothing special about the Ferrari head and he had all the workshop dimensions, etc. Also, like I said the driver's side head is perfect and showing great leakdown performance. Now I never checked leakdown before "running that head in" but it was done by same guy and is performing great. Makes me wonder if this "run in" need and tappet thing could be legit?

Thanks for following...

 

Thanks for the responses guys.

(1) The camshafts are absolutely in the right position (intake vs exhaust side).

(2) i can spin the lifter buckets by hand, underneath each cam lobe, when that cylinder is at TDC on its compression stroke. This would indicate to me that the valve should be fully closed but I had a ex Ferrari builder tell me that it may still be carrying pressure to the valve.

(3) The machinist said he checked the valve heights after the seats and valves were machined. I will double check with him.

Is the notion that the valves need to be "run in" feasible? I've read somewhere that Serdi cut valve jobs (for example) need to be run-in to get full seal. Perhaps I need to borrow the machine shops vacuum checker and put it back on the ports and check. Perhaps that seat has minor stone or cut marks which get fully smoothed upon running the motor?

Also, to clarify for anyone catching up on this long saga, both heads had the valve jobs but I had to pull the passenger side to have it re-worked as I screwed up on initial assembly and rotated the exhaust valves into the #6 piston when tightening the cam wheel. This is where this whole saga got deeper.

Does anyone think there is any merit to the notion that running in the engine is necessary to have the valve reach full sealing? Also, should I proceed with the compression check and go from there?

 

Thanks Flint (and others)! I will get it figured out. My hypothesis is that it is all fine. I think I need to get oil pumping it, lubing the valve guides and a few hundreds taps on the seats to allow the valves to find true center and seal as they are cycled. I will keep everyone posted.

I can't imagine that I repeated any errors on the timing this puppy. I don't make the same (or similar) mistake twice!

Merry Christmas to all!

- Jason

 

Heads not skimmed or machined.

I will do a compression check and move on from there.