De Lorean EuroTec

Small steps while I wait for a replacement camshaft.

Did you change the crank seal behind the flywheel? They are prone to leaking. There's a multi ribbed version (for your pleasure) that's a modified one to help stop it leaking out

Admin-bloke wrote:Did you change the crank seal behind the flywheel? They are prone to leaking. There's a multi ribbed version (for your pleasure) that's a modified one to help stop it leaking out

Already in line, waiting to be installed

A lot of “while I’m in there” stuff to consider.

If I’m going with used cams there is no use getting the rockers machined, and vice versa.

So either everything new, or all old stuff. But this is a slippery slope, if I get new cams, I might as well get some “performance” cams. To get the rough idle, if nothing else

How would you judge these lifters ?

Hi- I'm enjoying following your thread silently!

I've never built a PRV, but as the same principles apply to any engine.

I would not use these. The cost of head gaskets, oil, the pain of pulling the engine etc states that putting these back would be a false economy (if you wish to keep this as your car- if you are an unscrupulous **** looking to make a fast buck then bang them back in and pass it on...).

Similarly the cams you show are not good to go back in- it wont be long before these get eaten through, taking the lifters with them and putting lovely hardened "sparkle" all round the rest of the motor.

Just my thoughts. And I am Scottish....

I also suffer with "Scope Creep" when doing these types of jobs. You have to draw the line somewhere, but wild cams alone will not improve your motor, just make you poorer with a lumpy idle, non-standard motor that doesn't run as well as standard. Tho I am sure you know this already!!

Keep going!

Andy

Hi Andy, and thanks for your input.

A set of cams will set me back about 300 Euros, and 12 rocker about as much, while I can probably get a machine shop to grind down the rockers for a little less.

BTW you don't have to pull the heads to replace the cams and rockers, but you do have to pull the engine out of the car, so it is pretty labour intensive anyway.

m

Don't grind away any case hardening of the rockers. Put a wanted request out for cams and rockers as there have been many engines removed with block rot but heads and valve train have been ok.

If you do decide to get new cams or redoing ones, make sure you RUN the cam in correct ie not let the car just idle on startup.

Don't skimp on lubing every moving part up on reassembly etc

Are your other cams just as bad then?

Edit: RUN the cam in, not need

The state of the cams in my posession:

-one set of cams is very worn down
-one set has pitting from rust on most lobes
-one set har pitting from rust on one single lobe

I can't understand how the valve trains generally survive on these engines, about half of the (36) lifters I've removed had completely clogged oil supply.

The lifters in the photos are amont the best I have

Admin-bloke wrote:If you do decide to get new cams or redoing ones, make sure you RUN the cam in correct ie not let the car just idle on startup.

Edit: RUN the cam in, not need

What / how do you mean?
Most V8 pushrod engine camshafts are not pressure-lubed. Instead, the cam relies on splash oiling brought up from crankshaft movement. In that case revving the engine makes sense, but does this also apply to the PRV engine that has a reparate oil supply to each cam lobe/rocker?

Edit: RUN the cam in, not need

Running the cam in is a process on first time engine startup after fitting a new cam is to immediately run it between 2000 to 2500 for a length of time then slowly vary it up and down between say 1500 to 3000 rpm. This is an example of running in, but the procedure is specific to the cam manufacturer.

There is less pressure on the valve train at this speed than just let it at idle and the engine gives maximum oiling to the lobes to ensure the new components wear in with each other

You could read:

http://www.pipercams.co.uk/pipercams/ww ... lation.php

http://www.kentcams.com/information-faq.asp#