When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Well, that's interesting. I was dead set on getting an alternator conversion for a few reasons, extra power and simplicity being the main ones I guess. But the bracketry required is almost a £100 on it's own. This Dynalite could be the answer because it uses the original dynamo bracketry which I already have. . Hmmm, I will investigate further I think, thanks Glyn.
Well, that's interesting. I was dead set on getting an alternator conversion for a few reasons, extra power and simplicity being the main ones I guess. But the bracketry required is almost a £100 on it's own. This Dynalite could be the answer because it uses the original dynamo bracketry which I already have. . Hmmm, I will investigate further I think, thanks Glyn.
The other good thing about it is that the Jaguar pulley & fan are a direct fit. No messing around with shaft diameters. Everything aligns perfectly.
Glyn & Coventry Foundation.
we gave up. Seriously.
There are two dowels in the lower half of the bracket where the hex bolts go into the block. Even removing the hex bolts does not let the lower half of the bracket come apart or separate. The Shop Manual does not explain how to remove the dowels and we do not have the special tool.
The engine requires a complete rebuild based on what we discovered. The crankshaft journals are scratched and one has a spun bearing. Then the milk in the oil pan, head must come off , a stud can break, Wasn't prepared for this. The oil pump looks clean and like new, the timing chains area looks very clean but the rest is a mess.
We are going to try fitting the 4.2 engine.
Glyn & Cass: I removed the motor mount rubber donut (2 bolts) and then removed the entire bracket mount from the chassis (4 bolts).
It is not broken, what it is, is the angle that I took the picture originally from below the front member made it look like it was separating or had come unwelded. But no, it is solid on all 6 sides.
I marked it "D" for Driver's Side and painted an arrow to show the way it was oriented towards the front of the car before removing the 4 bolts. I have it with me and took a series of pictures. Have to edit them so tomorrow.
The bracket is higher on the REAR side and lower on the FRONT side.
Also the "seat" or "base" for the rubber donut is angled-welded downwards on the rear side, and angled-welded upwards on the front side. The difference in angles is approx.3/32nds front to back, i.e. front side is higher 1/16th + 1/32nd.
I saved the old donuts and they look like the engine weight had forced them forward, i.e., they are distorted at the center hole stud so the hole in the rubber is now oblong instead of round.
This drawing does not show all the Allen cap screws ~ only examples of direction. Do you have the main bearing cap off and out of the way and marked.
This was supplied as a complete assembly including seals.
These are all the parts.
Once you remove the 2 Allen Cap Screws that hold on the lower half of the seal cover housing it will just be hanging there by 2 hollow dowels. Give it a hard clout with a rubber mallet and it will come off with the dowels & the lower half of the seal. No special tools required.
Lift out crankshaft.
Then undo the upper housing 3 Allen Cap Screws (Centre screw C19686 is a different length). If stuck give it a hard clout with a rubber mallet and it will come off.
You're done.
Special tools or the crankshaft are only required when "rolling" in the new seals.
Sometimes better the devil you know. Have you any idea the condition of the 4.2? Are you sure it does not have the usual cracked block? Then you have rev counters & clocks etc. etc. to worry about. Does the DG take the torque or do you have to move to a Model 8 like the 420. The 35 did not take the torque of the 4.2.
I would rebuild the 3.8. Head studs don't break on 3.8's. They break on long stud 4.2 engines.
My car had done 90K miles & I reused the original studs ~ they are fine.
Last edited by Glyn M Ruck; May 18, 2021 at 09:52 AM.
I didn't know Glyn. With the understanding that I am not doing the work, neither of us could see the two vertical hex bolts holding both seal caps together and the engine was turned upside down on a stand, so regarding those two vertically oriented bolts we just didn't and couldn't see them. Really stupid I know, total lack of experience dealing with these engines, me especially. The service manual shows the two vertical bolts but at the time we found and looked at the illustration, all the three bolts "looked" horizontal. On closer inspection of the illustration, I can now see there are vertical hex bolts too. Too late, we gave up.
Here's the motor mount pictures and I hope it clarifies the orientation you and Cass were looking for:
another part we could not figure out how to remove and the Manual is not clear, is the timing chain sprocket or gear in order to release the crankshaft.
Jose the upper chain carrier must come off. Or you can cut the chain as I am sure you are going to replace it along with the upper chain and the chain guides and tensioners. Either way it all needs to come apart. You may look at your chain and see a opening link. Your mechanic surely understands that.
I'm following all this with great interest, especially the small things that often prove the biggest obstacles. I hope your experiences will make things easier for me in what hopefully isn't the too distant future. Though I've dismantelled and rebuilt a few engines, none have been Jaguar, which I guess says something positive about their reliability.
Jose posted (actually on the PS alternator/dynamo thread) a photo of his voltmeter taken from an early XJ. It looks good in the S type instrument panel. However, if you want to go more period (i.e. no battery symbol or colours on the scale), the early Range Rovers had a more 1960s style meter with the word 'VOLTAGE' for the label and a black and white dial.
Jose. Thank you for the pics of the engine mounting brackets. They look good. I speculate that automatics don't give them the hard time that manual cars do causing them to crack.
Glyn & Coventry Foundation.
We are going to try fitting the 4.2 engine.
You are going to create so much more work for yourself fitting the 4.2. Better to bite the bullet and hand the 3.8 over to an engine builder who might charge $3000 to get it up and running but you will have new pistons, re ground crank, new seals, re ground valves, new head gasket.. Throw in a new chain, fully cleaned water and oil ways and reassembled ready to drop back in. Basically a brand new engine.Then you can sell the 4.2 which is condition unknown for $3000 to pay for the rebuild. XK engines in good running order in the UK are selling for £2500 to £3500.
Think about it for a day or two before you take the wrong route Jose. The 3.8 might look bad now but it is easily fixed for the right price.
Cass I agree.
we spoke again this morning and decided to remove and take crankshaft to machine shop. Reassemble and get it running as is.
If later the head needs to be removed, it is easier with the engine in the car.
One thing I noticed, the engine looks very clean everywhere inside, I don't understand the milky stuff at the bottom of the sump. It is the only place where this mix of oil with possibly coolant is seen.
I am just exhausted from the job, having to drive 2 hours to and 2 hours from in Florida traffic is exhausting. The a/c in my van went out on the third trip doing 85 to 90 mph and everybody else was passing me at 100+ mph and that is slow. It is amazing that there has been no accidents at these speeds.
As far as the 3.8 vs. the 4.2. I prefer the 3.8. So here we go again.
I appreciate all the assistance I am getting from all of you.
I can hear some of you laughing at our ignorance but I have never said that I am an expert with Jaguar engines. I am not.. This is all new to me.
The good news? I am pressure washing the engine bay, replacing rubber hoses that have turned to chewing gum, new motor mounts, and still looking for an Alternator conversion. And now I know the difference between a Flex Plate and a Flywheel ! Haaa!
No one is laughing at you Jose. Anything is easy when you know how. You must find out where that water/coolant is coming from or you will mess up a newly ground crank & bearings. You must especially check the chaincase behind the water pump for corrosion pin holes. If you find any they are easily welded. You only need a few gaskets to do the check. I'm not talking about any new water pumps etc., but you must at least replace the lower chain. If you don't do the bottom chain & check the chaincase you will have to take the whole engine out again. Just give it some thought as Cass says. Timing chains are cheap. Only 10 Pounds. The alternator can wait. It's a top job. I know you are trying to do this on the cheap so I'm only suggesting the absolute minimum.
The milky stuff is at the bottom of the sump because the car has been in storage & oil floats on water due to differing density. So the coolant/water will be at the bottom of the sump.
Good luck!
Last edited by Glyn M Ruck; May 18, 2021 at 05:33 PM.
Yes. That's right or you can't get the chaincase out without the head off even if you cut the chains. Don't worry about taking the head off. A new gasket is only 36 Pounds. Fancier gaskets are only a few pounds more but Jaguar made them this way for a very long time.
The worse that can happen is you need some aluminium welding on the head ~ common & cheap.
All this will cost a lot less than your alternator that you can do later.
This is the heart of the car.
Last edited by Glyn M Ruck; May 18, 2021 at 07:14 PM.
If I may make a suggestion, and that is to do some measuring of the volume of the combustion chamber and the dome of the pistons and measure the actual compression ratio you have. I can send you a spreadsheet with the measurements and how to do them. Then you can determine the actual compression ratio you have and use an appropriate headgasket to obtain the compression you want.
The reason I say this is the 3.8 is much more susceptible to detonation than the 4.2, and the maximum compression a 3.8 can tolerate is about 9.2-9.3 on premium (91 AKI) fuel. If the head gets skimmed it it very easy to raise compression too high. The MLS gaskets are excellent, and available in variable thicknesses. Terry's Jaguar in MIchigan sells them. Once you have calculated the thickness you need they can either make it to order, or you can choose from standard thicknesses. They seal very well and don't need retorquing.
Ray Livingston on the Jag-lovers E Type list did much of this investigation about 15 years ago and developed the spreadsheet. I used it when my 3.8 was rebuilt and it now runs very well. I decided on a compression of 8.7 to give some margin for fuel when I got to sea level. I live at 3500' elevation and engine require less octane at higher elevations, so I could run midgrade fuel with 8.7 at my elevation.
When it comes to Octane tolerance on a new unfouled (no incandescent deposits) engine I have found with the XK that knock is more a function of timing curve than CR. With a CR of approx 8.8 & a perfectly set up distributor (41063A) running on 95 RON gasoline I don't get the vaguest hint of knock at any rev range. Static timing 7 deg BTDC at coast.
Twin SU ~ B head.
Jose is desperately trying to save money on this job.
Last edited by Glyn M Ruck; May 19, 2021 at 02:05 PM.
