Printable Version of Topic

Click here to view this topic in its original format

914World.com _ 914World Garage _ head gasket or no head gasket?

Posted by: ben1440 Jun 8 2005, 01:02 PM

so i am hearing that when putting back on my heads not to use a head gasket? what do you guys think.

also.....when i got the heads and push rods out, 3 lifters fell out and are mixed now. How bad is this?

Posted by: Joe Ricard Jun 8 2005, 01:59 PM

No head gasket. It WILL leak...
Just lap the cylinder to the head and you'll be fine.
Lifters bummer. well it ain't good but what are you going to do?
Great opportuity to look at that cam and see how screwed it already is. are your lifters flat anyway? Then again you might be ok if the lifters and cam are not really worn.

I smell a split case coming.

Posted by: Mike D. Jun 8 2005, 02:35 PM

bummer about those lifters... I did the same thing a few years back, engine ran for about a week, then I needed new cam and lifters and a total rebuild...

Maybe you could take the lifters to a machine shop for a resurface. don't know if that will help, hopefully someone here knows what will work.

-Mike D.

Posted by: Cap'n Krusty Jun 8 2005, 03:46 PM

QUOTE (Joe Ricard @ Jun 8 2005, 11:59 AM)
No head gasket. It WILL leak...
Just lap the cylinder to the head and you'll be fine.
Lifters bummer. well it ain't good but what are you going to do?
Great opportuity to look at that cam and see how screwed it already is. are your lifters flat anyway? Then again you might be ok if the lifters and cam are not really worn.

I smell a split case coming.

If you've had the cylinder heads surfaced, lapping will introduce a certain degree of randomness to the machined surfaces, NEVER a good idea. The machinist's mill is a LOT more apt to give you parallel surfaces than your hands, eyes, and some valve grinding compound. I dunno where this myth got started, nor why it refuses to go away! In addition, surfacing will decrease the volume of the head, so shimming the barrels will be necessary. Deleting the head gaskets will require even more shimming. Later VW 2 litre heads, and all the replacement VW heads, require the gasket be left out. You don't have later VW heads. Yours were designed to use a head gasket. I have customer engines with over a hundred thousand miles on rebuilds without head gasket leaks, so don't try that BS on me. As for the lifters, the question was put forth as to whether they're flat. Lifters aren't flat to begin with, they're convex, so if they're flat, they're worn. Assuming minimal to slight wear on the cam, I'd run 'em. If you have them ground, then there's the very real risk of them going away in short order. BTDT, many years ago. The Cap'n

Posted by: ben1440 Jun 8 2005, 04:12 PM

hmmm....well maybe time for the engine to see the engine doctor. I should have stopped after taking out the push rod tubes when i get home i will have to take a look at the lifters. I will see if i can get any decent pics of them. Thanks for the advice so far, much appreciated.

Posted by: bondo Jun 8 2005, 04:15 PM

To check for convexness, put two base to base.. they should rock slightly.

Posted by: messix Jun 8 2005, 04:17 PM

how much shimming is needed if no head gasket used.

is it a compresion issue? or interference problem?

if its compresion, how much is gained?

Posted by: nebreitling Jun 8 2005, 04:29 PM

QUOTE (messix @ Jun 8 2005, 02:17 PM)
how much shimming is needed if no head gasket used.

is it a compresion issue? or interference problem?

if its compresion, how much is gained?

potentially both. taking out the head gasket reduces deck (i don't recall how much, you could look it up) which raises compression. shimming under the barrels raises deck, which lowers compression. hi compression is great to a point (that point would be until you have to run race gas or until you start slamming pistons into valves)... you need between 40 and 60 thous deckheight to avoid the latter catastrophe. and definitely CC your heads after you flycut them -- you NEED to know this to setup your compression ratio.

n

Posted by: messix Jun 8 2005, 04:34 PM

thanx N

i have a '75 1.8 just wondering if this would be a way to gain 1 or 2 points of compression, from what is it 7.6/1 comp. to 8 or 9

Posted by: Joe Ricard Jun 8 2005, 05:36 PM

Looks like the capt caught menot being very good at writing again. Your right lifters shold noy be flat. It they are they are worn.

as far as bullshit well I have my preference and no metal head gasket for me thanks.

Last 2 motors I built were .037 deck hieght. One of them is in my car the "red neck racer" and you know how well that runs.