14 replies to this topic

[WiredbyWilson]

After a good chat with smart01 re head porting I have decided to tidy up the ports on my head myself before sending it th ethe machineists for guides and skimming.

So can anyone tell me the easiest way to get the old guides out with damaging the head? I don't have a vice or press by the way.

cheers

[PhilipGCaldwell]

i have heard of people putting them in the oven to heat it up then pressing them out. I wouldt fancy hammering them out incase it breaks the casting

[WiredbyWilson]

i have heard of people putting them in the oven to heat it up then pressing them out. I wouldt fancy hammering them out incase it breaks the casting

Thats what i was worried about - will make it very difficult porting with them in

And im sure the mrs would object to putting it in the oven!

[01smartc]

Porting is easier if left in, the tool you are using tends to get stuck in the hole left from the guides.

Just knock them out so they are level with the casting on the inlets, the exhaust are normally level anyway.

We use a special punch, put it in the guide and gently knock it out.

Chris

[WiredbyWilson]

Porting is easier if left in, the tool you are using tends to get stuck in the hole left from the guides.

Just knock them out so they are level with the casting on the inlets, the exhaust are normally level anyway.

We use a special punch, put it in the guide and gently knock it out.

Chris

So you mean grind and expose the exhaust port to the same degree that the inlet is as standard?

So you then with a suitable punch and patience i could tap them out enough?

[01smartc]

No i mean the guides are level with the guide boss in the exhaust port ... so kncok the inlets down level with the guide boss then start your grinding

Chris

[WiredbyWilson]

No i mean the guides are level with the guide boss in the exhaust port ... so kncok the inlets down level with the guide boss then start your grinding

Chris

Sorry i didn't explain very well.

The exhaust boss is much bigger in the exhaust port than the inlet port so would i be better porting then tappin gthe exhaust guide out to clean up the bit behind the guide (after removing most of the boss?)

[Turbo Phil]

There's no need to heat the head or anything like that, & you'll not break the casting knocking them out, It's easy enough to make up a suitable puch with a shoulder on for knocking the guides out & far far easier to port the head with them fully removed.

[eden7842]

is refitting them as simple as removing them?

[Turbo Phil]

Yes, basically. Make sure to set them to the correct height when istalling. {14mm}

[kez_19]

i made a tool for doing mine look here this worked perfectly and i didnt need more than a vice to press them out i wouldn't recommend banging them out as i think this can lead to cracks i believe its better to press them out slowly not shock them out

michael

[01smartc]

Turbo Phil - Really? You find it easier with guides removed? Doest you stone/carbide get stuck in the large hole? Just out of interest lol

Chris

Edited by 01smartc, 15 February 2010 - 06:56 PM.

[Pigeonto]

Turbo Phil - Really? You find it easier with guides removed? Doest you stone/carbide get stuck in the large hole? Just out of interest lol

Chris

This is what I have been doing ove the last couple of weeks too. I made a tool with a pilot to go into the guide which is a nice tight fit to support the walls of the guide just in case they tried to collapse.They arent all that tight really,but I have a large fly press so they may be actually.One important point I did learn is this;-If you dont need to renew them then only move them far enough down to do the porting then push them back because new ones WILL NOT BE CONCENTRIC WITH THE OLD ONES and the valve will be offset as a result, needing the seat re-cutting which is just a pain, worse if it is offset towards the other valve as they are too close together already

[Turbo Phil]

I could have worded it slightly better. What I meant was fully removed from the port, rather than trying to port it with the guide protruding into it.
As already said, if installing new guides the seats will need to be recut.

[WiredbyWilson]

I could have worded it slightly better. What I meant was fully removed from the port, rather than trying to port it with the guide protruding into it.
As already said, if installing new guides the seats will need to be recut.

The head will be going off to have unleaded exhaust seats fitted anyway so the seats will need to be recut - and if i knock the guides out I will just get the machine shop to refit them for me (think i was quoted for that within the £25 per seat cost for unleaded seats) plus the I know the guy quite well so hopefully can have a deal