Author Topic: hydro vs. mechanical camshaft..... (Read 5102 times)

jimbote · « **on:** July 15, 2007, 07:02:13 am »

what is the difference between a hydraulic and mechanical camshaft in the IDI engines....I have a good mechanical cam out of an 85 1.6 head ....was wondering if I could use it in my 1.9 IDI ?.....

zukgod1 · « **Reply #1 on:** July 16, 2007, 01:56:32 pm »

I dont know if you can use a Mech cam in a Hydro head.
I've heard of using a NA hydro cam in a TD hydro head however.

Just check your clearances on the bearing surfaces, they cant be that much differant being the same base engine.

I'm sure if I'm off at all somone will chime in.

dan

Black Smokin' Diesel · « **Reply #2 on:** July 16, 2007, 03:03:33 pm »

It has more to do with clearance between the lifters than the bore of the bearing surfaces.

Hydro cams are the same for NA, TD, ECO and even the 1.9TD.

RabbitJockey · « **Reply #3 on:** July 16, 2007, 03:45:41 pm »

as in they are all interchangeable, or that they are are all the same spec?

jimbote · « **Reply #4 on:** July 16, 2007, 04:38:06 pm »

I'm going to get out the calipers and the dial indicator and check these out....I have a 1.6 hydro cam with the pulley taper broken off (scrapyard eco turbo diesel) and I have an 85 mech motor.....maybe I cam come up with something interesting.....

Black Smokin' Diesel · « **Reply #5 on:** July 16, 2007, 05:22:30 pm »

Quote from: "Trev0rbr"

as in they are all interchangeable, or that they are are all the same spec?

All interchangeable.

zukgod1 · « **Reply #6 on:** July 17, 2007, 11:46:19 am »

Quote from: "Black Smokin' Diesel"

It has more to do with clearance between the lifters than the bore of the bearing surfaces.

What?

You can adjust the clearance between the cam and lifter's you cannot adjust the bearing clearance on the head without machining.

If you have either to much clearance or to little your gonna have problems.

dan

Black Smokin' Diesel · « **Reply #7 on:** July 17, 2007, 03:26:28 pm »

Quote from: "zukgod1"

Quote from: "Black Smokin' Diesel"
It has more to do with clearance between the lifters than the bore of the bearing surfaces.

What?

You can adjust the clearance between the cam and lifter's you cannot adjust the bearing clearance on the head without machining.

If you have either to much clearance or to little your gonna have problems.

dan

Sorry that came out wrong.

The hydro and solid cams don't have the same lobe profile (clearance between the cam and lifters). They probably have the same bearing surface bore.

Anyway has anyone even ever tried on solid cam on an hydro head and vice-versa?

Audi80 · « **Reply #8 on:** July 18, 2007, 01:05:29 am »

Hydro cam with solid lifters won´t work, too much valve lash... Have not tried vice-versa.

Fisher · « **Reply #9 on:** July 22, 2007, 12:06:33 am »

I just fired up a rebuilt 86 Hydraulic Engine with an early Mechanical Cam, works fine, it's the same.

Kudagra · « **Reply #10 on:** July 22, 2007, 09:14:12 am »

Quote from: "Audi80"

Hydro cam with solid lifters won´t work, too much valve lash... Have not tried vice-versa.

Using this info I would easily guess that vice-versa would yield not enough lash. But then again...I suppose lash is set by the hydraulic lifter.

Bah...just go hydro...who wants to mess with valve lash all the time.

Black Smokin' Diesel · « **Reply #11 on:** July 22, 2007, 11:23:49 am »

Quote from: "Audi80"

Hydro cam with solid lifters won´t work, too much valve lash... Have not tried vice-versa.

So there's too much clearance between the cam lobe and lifter. Does it mean that the solid cam in an hydro would mean more lift?

Fisher · « **Reply #12 on:** July 22, 2007, 01:45:55 pm »

No, it means they're the same Cam.

Black Smokin' Diesel · « **Reply #13 on:** July 22, 2007, 01:53:01 pm »

Quote from: "Fisher"

No, it means they're the same Cam.

Did you compare the two of them? It's not because it works that it's the same cam profile.

rabbitman · « **Reply #14 on:** October 24, 2007, 03:28:45 pm »

so will a hydro cam work on a solid lifter engine? I broke mine and have found a cheap hydro cam that I might buy. thanks