Cylinder head pressure testing/skimming in Bournemouth area

MikeT · Unread post by **MikeT** » 30 Jul 2008, 14:17

I'm having extreme difficulty locating a local engineering workshop to pressure test my cylinder head (and skim if ok).

Several local engineers recommend a place in Southampton but I've just come off the phone to them and they're quoted sky high prices - £53.94+vat for PT and £35.29+vat for skim.

Three others I found local-ish are all quoting about the same price which is far above the £20-£30 I've been told it would cost.

handyman · Unread post by **handyman** » 30 Jul 2008, 17:54

Hello Mike, the prices you have got look quite in line with the work involved in skimming and testing the head.

You have to bear in mind the time taken to setup your head in the test rig and on the bed of the mill. With this type of work, if you pay peanuts, you may not get a very accurate job.

Handyman

citronut · Unread post by **citronut** » 30 Jul 2008, 19:39

as i said in your earlier postting i have a presure test rig i biult myself, but im in st leonards on sea
east sussexif you can collect and drop back after use you are welcome to borrow it,

it consists of a sheet of 1/4 inch thick steel with holes cut by plasma cutter for each of the combution chambers, 10 holes drilled for boltting it to the head (at head bolt points) two smaller blanking plates to capp the water ways (one on end of head the other at the left front face), the one on the end of the head needs a metal tyre valve fitting, you will also need a sheet and two small pieces of very thick rubber to use as a seal between each of the metal plates,

then you fill a container big enough to submerge the head with water, with an air line conected to the tyre valve , pump it up to around 80psi and check for bubbles

regards malcolm

MikeT · Unread post by **MikeT** » 31 Jul 2008, 11:36

Handyman, I appreciate what you're saying, I'm just disappointed because my budget isn't so flexible - particularly if it proves the head is scrap.

Thanks Malcolm, that's a very kind offer though you're a fair distance from me. It would be cheaper for me if I could test it there as it will save me a return journey and you could supervise me

citronut · Unread post by **citronut** » 31 Jul 2008, 13:15

ok Mike thats a possibilaty if you need to, the other way of looking at the cost of getting it done near you is, firstly its cheaper than prepairing the head and re/fitting it only to find its tsill go coolant troubles, also its will probably work out cheaper than comming all the way over here, not that i wouldnt like to meet your or anything,

if you did drop by the other thing i would like you to bring would be a suetable sized container to submers the head in as i cant think of one i might have off hand

regards malcolm

MikeT · Unread post by **MikeT** » 31 Jul 2008, 14:05

I've found a few distant workshops that will test it for less so things are looking up.

Being near the coast, there's also an abundance of marine engine workshops (that might offer head testing?). I'll try calling a few later to see what the possibilities are there.

What bothers me most is not knowing what caused the original fault - coolant overpressurising. Research suggests a cracked/corroded head which means more expense on top of the testing & skimming fee if it can be repaired.

citronut · Unread post by **citronut** » 31 Jul 2008, 18:21

as i said earlier Mike the sealing ponits on the gasket,head and block looked abit discoloured in a couple of places in yoiur picys, the almost certainly was a point were the gasket had failed
regards malcolm

MikeT · Unread post by **MikeT** » 31 Jul 2008, 19:22

To my untrained eye, I just saw oil streaks, dirty marks and peeling sealant revealing a stainless steel gasket layer that became brass coloured where it meets coolant channels.

Whether there were sealing issues, I didn't think it worth debating as these would have been cured by a skim and new gasket. However....

I've just been inspecting the head again now after cleaning and have found all four precombustion chambers have cracks coming from the openings.

EDIT: I assumed these cracks were terminal or signs of invisible damage that could be terminal but I've just seen a S/H head on ebay that says it has "the usual cracks" at the pre-chambers. Are they a concern or not? I don't know.

Now, this head is off an LDV Pilot and is currently fetching 99p with less than an hour to go. It does say it's for a non-turbo, so is there a difference? Please respond soon in case I miss this opportunity.

citronut · Unread post by **citronut** » 31 Jul 2008, 23:33

it is very common for these chambers to be cracked, it dose not seem to affect the running,

the discolouring i was talking about is more noticable on the head face, you can see the nice clean shiny line around each of the combustion chambers, this line dose not appear to make a complete circle around each of the chambers, it disapears between 1 and 2 then the same between 3 and 4, this tells me the gasket was not forming a gas or coolant tight seal, at the point it is discoloured it is alsop along side water ways,

even after all that it is faulse econamy not to have it presure tested

regards malcolm

MikeT · Unread post by **MikeT** » 01 Aug 2008, 11:19

It's difficult for me to imagine those cracks are "normal" and nothing to worry about but I'll take your word for it. Under magnification they look eroded rather than stressed.

I agree it's a false economy not to test the head but it's also a waste of money just to be told it's scrap so I'm in two minds about that. I'd feel better gambling the money on a 2-1 horse

Talking of hedged bets, I'm keeping an eye out for a replacement head that I could buy for less than the price of a test and skim.

I'll continue ringing around to see if I can get the price down a bit. I've seen companies up north that are far cheaper so there must be someone down here I can take it to.

Unread post by **CitroJim** » 01 Aug 2008, 11:47

Mike,

I reiterate what malcolm has said, don't worry about prechamber cracks. "They all do that sir!"

My local man charges just under £30 for a skim and pressure test so you can find cheaper if you shop around... Take a trip to Woburn Sands and visit Woburn Abbey whilst they sort your head out

A nice day out. Come over and see me whilst you're up this way

MikeT · Unread post by **MikeT** » 01 Aug 2008, 12:12

Again, another kind offer but I have to consider distance very carefully considering fuel costs.

When you got the head tested did you have to remove everything - cam, valves, injectors, glowplugs etc and did it have to be clean?

Unread post by **CitroJim** » 01 Aug 2008, 12:32

Everything but the valves Mike although I did remove the valves initially. The head man tells me they prefer the valves left in to assist with pressure testing.

I appreciate the cost of fuel to come up my way. The cost of the skim plus the petrol you'd consume makes your local ones look an economical proposition

MikeT · Unread post by **MikeT** » 01 Aug 2008, 13:11

I now wondering how much fuel it would cost on a 125

Have you still got that sub amp in your loft Jim? 8)

Unread post by **CitroJim** » 01 Aug 2008, 13:31

MikeT wrote:Have you still got that sub amp in your loft Jim? 8)

Yes. A sub on a 125

The mind boggles

I know, you want to make it sound like a Harley