Jalpa engine rebuild - Page 4

Jalpa_Aus · #31 (**permalink**) 05-11-2008, 03:40 AM

Time to get started on the CV boots, I ordered 4 CV boot kits from George Evans complete with boot straps & grease cost approx $90 US.
First problem I had was getting the 36mm nuts off the end of the drive shaft. As in Picture 1 I had it mounted in the vice probably would have been Ok it it was still in the car but I was unable to provide enough torque to get the nut undone, I had a 3/4 inch socket and extension bar with a pipe on the end of that and was about to rip the vice off the bench

. I then took it down to the work shop to get them to loosen it they used a 3/4 rattle gun to get if off.
Once back home I could take the nut off and pull the shaft out the back of the hub as in picture 2. I have also pointed out that there are 4 allen key bolts that need to be undone and then the joint splits where the green arrow is pointing, I have already done this in the next picture.
In the third picture I have already removed the two metal retaining straps that keep the rubber boot in place, I was actually surprised at how good the rubber still was on these old boots. I then removed the sirclip from the end of the shaft to allow me to tap the CV joint off.
In picture 4 I am using a aluminum drift to tape the CV joint off the end of the spline, there is a washer on the inside so have to remember to put that back on before installing the joint

Once I had it all apart it was time to degrease everthing and get it cleaned up. After the first degraese I have oiled all the metal parts so they dont rust may be a week or so before I can get back to it. I will degrease again before repacking the bearings.
I then had to clean up all the hubs and drive shafts ready for painting with POR15.
In picture five you can see the hub once it has been wire brushed then preped with wax & grease remover. Some of the parts I won't paint due to the them having shimms and any extra paint may change the tolerances, a couple of places I did paint accidently I will sand off prior to installation, anything that is not painted will be installed with a coating of high temperature bearing grease to stop rusting.

Jalpa_Aus · #32 (**permalink**) 05-28-2008, 12:11 AM

People,
I was wondering if any one has the Jalpa inlet and exhaust valve tappet clearances? The work shop rebuilding my engine has been unable to find the settings in the Urraco 3000 engine rebuild manual I supplied them with. I suspect they will be in there somewhere but don't have a copy at home to check.

TIA

Mike

raymond · #33 (**permalink**) 05-28-2008, 03:01 AM

I think it's in the owners manual, see jalpa-homepage.
0,25 inlet and 0,50 outlet the same as on the QV.

Manual:
Valve clearance (with cold engine)
-inlet
-exhaust
0,45 mm
0,5 mm

I'll cross check with my other sources.

Jalpa_Aus · #34 (**permalink**) 05-28-2008, 04:42 AM

Raymond,
Thanks for the quick reply, if you manage to confirm that would be good

Thanks Mike

Laust · #35 (**permalink**) 05-28-2008, 10:02 AM

According to the "Driver's Handbook" (Jalpa P118/B) the valve clearance specifications are:
Inlet: 0.45 mm
Exhaust: 0.35 mm

raymond · #36 (**permalink**) 05-28-2008, 10:55 AM

Laust, this is for sure exchanged, exhaust is always more than inlet.
P300 Urraco says 0,45mm, QV says 0,35 and 0,45.

SO exhaust 0,45mm seems to be accurate, 0,35-0,4 for the inlet.

Laust · #37 (**permalink**) 05-28-2008, 09:56 PM

Raymond,

Well, specifying valve lash (clearance) is not straightforward. If the valve and cylinder head had the same temperature the valve lash would increase with temperature, due to the higher thermal expansion coefficient of aluminum (cylinder head) vs. steel (valve). Although the exhaust gas heats the exhaust ports, the exhaust valve likely gets quite a bit hotter, but maybe the net result is no clearance change between hot and cold engine.

The Jalpa engine has sodium filled exhaust valves (if nobody has changed them), which runs cooler than solid valves, so everything equal they should likely have a slightly smaller clearance than the solid valves. Did they change from solid to sodium filled exhaust valves from the Urraco to the Jalpa?
The early 4L V12 engine with solid valves has a specified valve lash of 0.25 mm on both intake and exhaust.

Lastly, when I measured my Jalpa’s valve clearances they were very close to the specifications I gave in the previous post, so I left them alone and they have worked fine since (even with 10 psi turbo-charging).
If I ever were to change the exhaust valves to solid stainless, I would increase their clearance to 0.45 mm.

jalpa_mike · #38 (**permalink**) 05-29-2008, 09:04 AM

Quote:

Originally Posted by Laust

According to the "Driver's Handbook" (Jalpa P118/B) the valve clearance specifications are:
Inlet: 0.45 mm
Exhaust: 0.35 mm

I wonder if there is a revision to the Jalpa Drivers Handbook? This is what mine says:

Inlet: 0.45mm
Exhaust: 0.5mm

Jalpa_Aus · #39 (**permalink**) 05-30-2008, 12:16 AM

Thanks all for the replies,
I received an email from George evans this is the guy that did Ross's engine rebuild. He advised me that the clearance for both the inlet and exhaust is .018 of an inch which is 0.45mm. I have advised my workshop to use that setting, George has rebuilt many Jalpa engines over the years and I trust his judgement.
As Jalpa_Mike has mentioned there are a few different figures around I also had the
Inlet: 0.45mm
Exhaust: 0.5mm
settings in my hand book, from memory the Urraco 3000 engine workshop manual has the settings both at 0.45mm

THECARREAPER · #40 (**permalink**) 06-01-2008, 03:05 PM

good to know, thanks for posting.

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