P6B S Project Car

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Whats the proper fix for the lack of a crankcase breather at the rear of a 3.9 block, going into the P6B?
I stand under correction, but the 3.9 onwards didn't have the breather at the back of the block. They draw air from the cleaner in one tappet cover and it is sucked out the other side into the intake stream.

Something like this...
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They don't, but if you want to retain the stock P6 breather and ventilation system you can fit one. I have since moved from the SU induction system to a four barrel with a PCV set up but have still retained the rear breather and my engine now gets fresh air from the rear as well as the front fitted rocker cover breather.
 
If you use SD1 rocker covers you can dispense with the "T" pipe at the block, but you will need to use the SD1 flame trap and pipes.
 
As part of the 3.9 rebuild I thought nice SS bolts on the timing cover & water pump would be good. Boght a pack off fleabay...short water pump bolts are 1.25" , should be 1.125. Some of the others I cant work out where they go. Some of the packs on fleabay seem to have far too many bolts, and also wrong length. Going to use an SD1 timing cover, but I doubt the no of bolts changed. From the book I make the count 13 in total. Some packs run from 15 to 20 bolts. The parts book only lists 4 cover fixing bolts separate from the water pump set of 9, which seems low? Parts book I have is wrong on this page - normally if there are different parts used on different chassis or engines they put numbers inside little circles, and explain the differences in notes below; different from numbers in brackets indicating qty required. On the long timing cover bolts the numbers are in circles, but they should be in brackets - 2 x 3.82", 1 x 3". The short bolts are listed correctly, 5 bolts total. There are no notes about model differences on this page (11-13), just 'Applicable to 3500 and 3500S models".
 
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Things are progressing.
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I have a spare dizzy from a 10.5CR engine, cleaning and rebuilding it. Planning on running 9.35CR pistons in the rebuilt 3.9L. Checking this dizzy's advance curve vs that of a 9.25CR 3.5L, I find the same slope to ~1500rpm, then the 10.5 slope is the same angle, but higher by a couple of degrees. Is it safe to assume this wont cause problems (pinging) as long as I use a premium fuel? Irritating that advance specs never seem to use the same rpm points....
PS- Although there is little detectable play in the bottom end of the dizzy shaft, its well marked (similar to a worn rocker shaft) - is it worth trying to get some oil into that area ? Small hole drilled in the timing cover in that area and another in the dizzy casting ?

Which are the 'wet' bolts - the long ones through the water pump into the block?

thanks
 
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Dizzy - going to drill an oil hole in the low end of the dizzy body, just above the bottom bushing, and a hole in the timing cover part that the dizzy stem goes into to try to get some oil into that bottom bush. The wear on the shaft reminds me of a worn rocker shaft. The dizzy housing has a slightly thinner section between the top area (with the Oring on it) and the bottom where its a nice fit in the timing cover, so a bit of oil can go in there through the hole. Probably insignificant with the miles I will do, but it cant hurt.
 
The 94 disco 3.9l engine came with a sump - full depth to the back, which is OK as my car is a manual, and the more oil the better IMHO. Checked the sump plug - BSP.
 
Saw elsewhere a video of a timing cover mod to spray oil on the dizzy drive gear.
Our covers are different, but the principle looked useful, so am trying it. We seem to have a casting boss on the side of the relevant delivery hole from the cover into the block that would make the drilling quite a bit longer. Elsewhere cobraboy mentioned trying it with a 0.020" drill (~0.5mm), but these are a bit thin on the ground, as well as easily broken, so I am trying it with a 1mm drill (0.039"). To put the size in perspective, the area ratio of the big hole (1/2", 12.7mm) to a 1mm hole is 161:1, so I doubt much volume or pressure will be lost. I drilled 2/3 of the way through with a 1/16" drill then switched to the nice new sharp 1mm drill in the pin vice - only a minute or so. Not sure if the jet will get past the cam gear, but it should put oil where there wasnt any before.
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Also have seen clips of drilling the oil galleries larger. I had thought ours were already 1/2", but not in my example. Couldnt get a 1/2" started, even a 12mm was difficult. Finally managed to get an 11mm drill through the main output gallery, removed quite a bit of metal. Thorough wash and blow out coming up.
 
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After getting the 11mm drill through I tried the 12mm. The drill is not the sharpest , so it was a bit of a struggle. I did a bit of dressing on the cutting edges and finally got it all the way to the end. The bore was a bit rough so I gave it some attention with wet-n-dry wrapped on a piece of dowel. Got to be better than it used to be. Area ratio of the bleed hole is now up to 144:1 - not as good as the 161 with a 1/2" hole but still good...IMHO. More cleaning of the inside and a hose out, looks much better now.
 
Working on the SD1 front cover, oil pump. Got new gears, relief valve piston and spring. Fitted the new gears, checked fit - ~.0035" proud, book says 2.8 to 5.8 thou, so in there. Fitted new gasket, snugged up the bolts, shaft turns nicely, so that is all good.
Rebuilding a dizzy, I found one of the vac advance unit fixing screws is a self tapper. Not going back in. The other one measures as 1/8" dia, 40 tpi...commonly referred to as 5-40 UNC. Cant seem to find any in my modelling kit, so might have to buy some and shorten to suit.
 
More progress..
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Should be home early next week! The angle of the sidelights is a wide angle lens artifact. Very pleased with the quality of the work - all the panel gaps are good, the damaged side chrome strip is spot on.They started it and remarked on how well it fired up and ran. Also remarked on it taking a while to get the bonnet to meet the striker correctly. The bonnet edge rubbers were all just doing their job.
Now, whats this tool ?
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The two on the mat are for dent removal, the fixing on the door for a puller, the light to show up ripples / dents
 
Very clean and tidy shop, judging by those photos. Looks like good work is being done.
What is the tool in the door for?
 
The cleanliness of the workshop impressed me a lot before I committed to send the car there.
Dont know about the horizontal bar attached the Cayenne door - suspect its to stabilize the door while its worked on. The bent rod on the floor is for snaking inside the door and pushing out dints from inside. There was another guy with the special light working on the other side, and it was very effective in highlighting very small dints in the panels.
The striker panel on my car looked like new - fresh looking spot welds, all smooth , no signs of fixing at all. Note that they masked the engine and the inner guard stickers and repainted all the black bits. Very very thorough mob. Glad it was donre on somebody else's insurance.
 
She's home again! Looks better than ever.
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Minor irritation - swapping front tyres, they seem to have refitted the front wheels with a rattle gun, and lost some of the wheel nut washers....on their case about it. Now to resume rectification of minor issues - electric fuel pump plumbing etc.
 
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