BX Head Job

[twm]

Hi Guys

I was just reading the haynes manual that says you are not suppose to surface the head.

Is that true, mine may be cracked or warped, should have it off tomorrow.

(re bx steam engine thread) BX16trs

I was going to send it somewhere for repair, but if it cant be machined then I will have to get a replcement I suppose, any advice would be appreciated.

Cheers
Terry

 

[Alan S]

If the guy doing the head machining knows what he's doing it's no real drama.
The thing that can trap you is if the valve faces are left dangling down far enough to kiss the pistons @TDC. We did a 16V engine a couple of yrears back and it had to be planed also. In that instance we also fitted oversized valves but had the piston faces filleted out to compensate.
Haynes is always on the overly conservative side mainly to cover their asses if there is a stuff up.
Mention it to whoever is doing the head and if he's worth his salt, it shouldn't be a drama.
I can't speak for PSA engines, but on some, a thick head gasket used to be available to compensate.


Alan S

 

[Dave]

On an 8 Valve engine you have nothing to worry about. Just tell them to take as much of as they need to make it flat, you can always use the extra compression. Piston to valve clearance shouldn't be a problem either. Shouldn't need more than a light skim too be flat anyway. You may wish to double check exact measurements with PeterT, as I have never had a 1.6 head off before. We have shaved more than a mm off 1.9 heads in the past though.

Dave

 

[Alan S]

Dave,

Remember I was asking a question a couple of weeks back about the differences between a 1.6 and a 1.9 head and we came to the conclusion that the 1.6 was a higher C/R and had a much smaller combustion chamber, which is why I suggested a bit of caution with valve faces.

Alan S

 

[Dave]

Alan - the 1.6 head has a 34cc combustion chamber. I have a 1.9 head with 34ccc combustion chamber over the high compression pistons. This head has also had about.2mm shaved off and at one stage I had a .5mm copper head gasket on (about 1mm thinner than std). Combined also with a camshaft with much higher lift than standard.
So if i couldn't hit the pistons with that combination i'm fairly sure a quick skim isn't going to cause any issues.

Cheers - I actually had to think about that

Dave

 

[twm]

Thanks Guys

Is it worth trying to find a replacement, I am fairly sure this one will be cracked dur to steam out exhaust and oil in water, funny the little bugger still starts and runs, quite amazing relay if you saw how much steam came out the exhaust.

Oh and while im down there do you reckon its worth doing anything with the cam?

Cheers
Terry

 

[Dave]

A few guys on here have spare heads and even heads that are ported etc that they would let go of. Just post in the parts wanted section and i'm sure a few people will contact you.

Dave

 

[Alan S]

I wouldn't worry about it until you get the head off and take a close look.
Providing you didn't do anything silly like pour a gutful of cold water into a red hot dry system, you may be OK. These bloody things take a lot of killing believe me (contrary to folklore and myths) :crazy: :crazy:

Alan S

 

[twm]

I wouldn't worry about it until you get the head off and take a close look.
Providing you didn't do anything silly like pour a gutful of cold water into a red hot dry system, you may be OK. These bloody things take a lot of killing believe me (contrary to folklore and myths) :crazy: :crazy:

Alan S

No didnt put cold water in hot motor, but it did run dry, just had the air fixed so I thought the aircon guys bumped a wire. It started missing after I stopped.

I take your point though I wont know exaclty until "off with its head"

Thanks again

 

[twm]

No didnt put cold water in hot motor, but it did run dry, just had the air fixed so I thought the aircon guys bumped a wire. It started missing after I stopped.

I take your point though I wont know exaclty until "off with its head"

Thanks again

BTW I got the head off and there is diffinatley a blown head gasket, into the water chambers, not sure if this would also send some water to the oils as well.

I found a motor and box, and this will actually work out about the same a doing up the head alone, so a motor swap is about to happen.

Looking at the interanls of the bx motor I am fairly impressed with the design.

I will probably have the head pressure tested for amtter of interest.

Cheers

 

[Alan S]

Water in the oil can also come about due to leaking in the liner seals, an "O" ring that sits at the bottom of the liner and seals onto the actual block.
We had a 16V engine at a mod shop for a while and it was the topic of conversation with mechanics and guys associated with race cars and the like due to it's designs which in some cases were described as above some of the competition engines they d modifications on and some of it described as "more of a work of art than a piece of machinery."
Anyone with any mechanical knowledge is usually gobsmacked at what the find inside these engines.
A word to the wise though; check the engine carefully for internal corrosion which is a weak spot with these early 16Trs engines. They can eat through between cylinders 1 & 2 and at the front from what I've seen. It appears to be caused by a breakdown in earth continuity and in some instances can be so big as to render the engine U/S. Look carefully for signs of white chalky marks running down the outside of the block and if found, don't instal the engine as it will blow for sure. Be certain ti use a good quality coolant and keep it fresh from when the car is reassembled onwards.

Alan S

 

[twm]

Water in the oil can also come about due to leaking in the liner seals, an "O" ring that sits at the bottom of the liner and seals onto the actual block.
We had a 16V engine at a mod shop for a while and it was the topic of conversation with mechanics and guys associated with race cars and the like due to it's designs which in some cases were described as above some of the competition engines they d modifications on and some of it described as "more of a work of art than a piece of machinery."
Anyone with any mechanical knowledge is usually gobsmacked at what the find inside these engines.
A word to the wise though; check the engine carefully for internal corrosion which is a weak spot with these early 16Trs engines. They can eat through between cylinders 1 & 2 and at the front from what I've seen. It appears to be caused by a breakdown in earth continuity and in some instances can be so big as to render the engine U/S. Look carefully for signs of white chalky marks running down the outside of the block and if found, don't instal the engine as it will blow for sure. Be certain ti use a good quality coolant and keep it fresh from when the car is reassembled onwards.

Alan S

Hi Alan

Yes good advice, it all looks ok and the old motor was ok until the overheat issue, which I might add, was not the cars fault.

I intend on keeping up with the coolant, I am pretty sure that the engine is ok from what the owner said. He did an upgrade to a 19, and said all was well with the engine and box. :wink2:

Cheers