Patchy's Fawlty Towers risk management. Enter at own risk
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Re: Patchy's Fawlty Towers risk management. Enter at own risk
Could the valves been sticking down? Was it just cams and a deck or are there new guides as well?
NA8: N/A 200whp | Haltech | Skunk2 Intake | S90 TB | RCP | 5 speed c/r dogbox | 4.78 diff | AST Shocks
Barbs L: 64.12 | S: 58.62 | Collie: 49.72
Barbs L: 64.12 | S: 58.62 | Collie: 49.72
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Re: Patchy's Fawlty Towers risk management. Enter at own risk
Original guides.
Satans Ride called F33nix the resurrected NA6
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Re: Patchy's Fawlty Towers risk management. Enter at own risk
Sight.
So I had a few Single malt scotches last night. Maybe I should have spent that money on new valves or Lifters.......
The piston is hitting the deck. There is ever so slight pitting on the head surface as well as the piston. Ok that will be sorted.
Valves may be bent. Not sure.
I checked clearance with blue tack. All ok. But it doesn't explain the pitting on the pistons.
The picture you see above is the 2 valves moving at a diffferent height.
I swapped the lifters and it made them even. But look like they are not sealing.
A few others have the same issue which suggests bent valves.
However when cam is removed. All valves seal and appear to be sitting on thier seats correctly.
I have no issue replacing valves. But the other concern I have is with the HLA......
I was concerned with the base circle of the cams being inconsistent . However I put the standard cams back in & it's just as problematic.
Just researching the HLA's
So I had a few Single malt scotches last night. Maybe I should have spent that money on new valves or Lifters.......

The piston is hitting the deck. There is ever so slight pitting on the head surface as well as the piston. Ok that will be sorted.
Valves may be bent. Not sure.
I checked clearance with blue tack. All ok. But it doesn't explain the pitting on the pistons.
The picture you see above is the 2 valves moving at a diffferent height.
I swapped the lifters and it made them even. But look like they are not sealing.
A few others have the same issue which suggests bent valves.
However when cam is removed. All valves seal and appear to be sitting on thier seats correctly.
I have no issue replacing valves. But the other concern I have is with the HLA......
I was concerned with the base circle of the cams being inconsistent . However I put the standard cams back in & it's just as problematic.
Just researching the HLA's
Satans Ride called F33nix the resurrected NA6
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Re: Patchy's Fawlty Towers risk management. Enter at own risk
Stan, except for 0.75mm head shave & 0.60mm thinner Cometic head gasket, isn't this so far much the same setup you used to run without issue (ECU aside)?
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Re: Patchy's Fawlty Towers risk management. Enter at own risk
correct.
OEM ECU have not installed the Megasquirt as yet.
Once I get the engine running right I'll attack the electrics to get rego. MSPnP2 will not be installed for a few months
OEM ECU have not installed the Megasquirt as yet.
Once I get the engine running right I'll attack the electrics to get rego. MSPnP2 will not be installed for a few months
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Re: Patchy's Fawlty Towers risk management. Enter at own risk
Correct me. The pistons should not have valve indentations?
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Re: Patchy's Fawlty Towers risk management. Enter at own risk
I don't recall seeing them previously.
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Re: RE: Re: Patchy's Fawlty Towers risk management. Enter at own risk
bruce wrote:Correct me. The pistons should not have valve indentations?
They are not flat tops if that's what you mean.
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NA6 turbo - 140kw atw - not the most powerful but so much fun 
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Re: Patchy's Fawlty Towers risk management. Enter at own risk
The exhaust indentations in a piston are smaller than the intake indentations to correspond with valve size. You need to make sure you get the piston around the correct way when installing them. In most cases, if piston to valve clearance is wrong with a high lift / duration cam (eg bad timing) then you'll know it as you turn the motor over. It won't turn by hand or even whilst cranking, unless it's just touching.
I'm trying to think of a reason why the valves would be sticking where before they weren't. The piston hitting the head is a separate issue unless the piston is also hitting the valve. Even a small hit could bend the valve and make them stick, but really there should be enough space between the piston and valves to clear.
The other possibility is that the hydraulic lifters are being messed up by the larger lift, smaller base circle cams. I'm pretty sure the oiling supply in the lifter bore is meant to feed into the grove in the lifter when the valve is at closed so if that isn't aligning properly, maybe the lifter isn't getting the required oil flow to operate and it's collapsing. I'm not sure how that would cause the valve to stick or be hit by the piston though.
I'm trying to think of a reason why the valves would be sticking where before they weren't. The piston hitting the head is a separate issue unless the piston is also hitting the valve. Even a small hit could bend the valve and make them stick, but really there should be enough space between the piston and valves to clear.
The other possibility is that the hydraulic lifters are being messed up by the larger lift, smaller base circle cams. I'm pretty sure the oiling supply in the lifter bore is meant to feed into the grove in the lifter when the valve is at closed so if that isn't aligning properly, maybe the lifter isn't getting the required oil flow to operate and it's collapsing. I'm not sure how that would cause the valve to stick or be hit by the piston though.
NA8: N/A 200whp | Haltech | Skunk2 Intake | S90 TB | RCP | 5 speed c/r dogbox | 4.78 diff | AST Shocks
Barbs L: 64.12 | S: 58.62 | Collie: 49.72
Barbs L: 64.12 | S: 58.62 | Collie: 49.72
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Re: Patchy's Fawlty Towers risk management. Enter at own risk
Did some measuring
Head is 133.54mm.
That's 0.26mm thinner than recommended
Mmmm probably not going to do much about that.
Pistons are 0.45mm above deck.
That should give me about 0.75 mm or 0.03 thou quench? Also a bit tight.
Head is 133.54mm.
That's 0.26mm thinner than recommended
Mmmm probably not going to do much about that.
Pistons are 0.45mm above deck.
That should give me about 0.75 mm or 0.03 thou quench? Also a bit tight.

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Re: Patchy's Fawlty Towers risk management. Enter at own risk
Did you ever get a bit of a rumble in the bottom end? 

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Re: Patchy's Fawlty Towers risk management. Enter at own risk
Not sure what you mean 

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Re: Patchy's Fawlty Towers risk management. Enter at own risk
If I saw that, my bottom end would rumble!
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Re: Patchy's Fawlty Towers risk management. Enter at own risk
So after a bit of messing around & checking the seal of valves, I recieved another set of HLA's
Unfortunately they were not much better than my own. I managed to find 5 useful ones out of a set.
So I figured I should really just take one apart. I was a bit worried. But it's a walk in the park.
Quite easy to take apart clean & get unstuck. Yepeeee!!!!!!
So out of 2 sets of 2nd hand ones, I've now got one full set of working HLA's
Got about 4.5mm of play in them give or take a little.
So it was then decided to give the head another clean before reassembly

I'm letting it dry for a few hrs
All the intake valves in order with a bunch of spare not working HLA's

Unfortunately they were not much better than my own. I managed to find 5 useful ones out of a set.
So I figured I should really just take one apart. I was a bit worried. But it's a walk in the park.
Quite easy to take apart clean & get unstuck. Yepeeee!!!!!!
So out of 2 sets of 2nd hand ones, I've now got one full set of working HLA's
Got about 4.5mm of play in them give or take a little.
So it was then decided to give the head another clean before reassembly

I'm letting it dry for a few hrs
All the intake valves in order with a bunch of spare not working HLA's

Satans Ride called F33nix the resurrected NA6
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Re: Patchy's Fawlty Towers risk management. Enter at own risk
After getting a good clean this morning it was time to reassemble
Engine assembly lube is sticky & dirty.

Cams are back in and it is now ready for a trial fitting to check valve clearance. That's if the head gasket ever turns up. It must have turned left behind Pluto & as we speak, probably heading towards Andromeda, our neighbouring Galaxy.
Engine assembly lube is sticky & dirty.

Cams are back in and it is now ready for a trial fitting to check valve clearance. That's if the head gasket ever turns up. It must have turned left behind Pluto & as we speak, probably heading towards Andromeda, our neighbouring Galaxy.
Satans Ride called F33nix the resurrected NA6
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