head gasket failure prompts winter rebuild
Discussion
hey guys,
here's a little update on the winter rebuild. sorry i've been so quiet, busy times.
spent the last month or so cleaning up the various engine parts ready for the rebuild. in between xmas and new year i took a little trip to Jetstream to pick up all the gaskets and gear linkage parts.
I've also started to cut the tunnel ready for the Jetstream gear linkage upgrade and wiring in my data logger.
I was planning on getting the original pistons cleaned up and ceramic coated but when tracksport were cleaning the ring grooves one of the pistons broke apart. this explains the pressure that was getting into the sump when i was at Silverstone.
here's a pic of the bit that broke off. it was the only piston which was damaged
the heads are back from the engine builder. They were leak tested and checked for flatness and all ok :-). the valves were ground in and the valve seals were replaced.
the exhaust has just come back from CamCoat and looks the business.
Andy from Tracksport travelled up yesterday to help me get the engine back together. We honed the bores and put the new Mountune forged pistons, arrow conrods and uprated new bearing shells together.
we then hit a bit of a snag. we fitted a couple of the pistons to the block and turned the engine by hand to make sure everything was ok and when the pistons got to the bottom of the stroke the engine would not turn further. on further inspection we could see the bottom of the new pistons was contacting the counter weight on the crank (on both pistons we had fitted).
We then compared the new pistons to the original Noble ones and the original ones are cast pistons but then someone has machined away material around the gudgeon pin to prevent this clash. Frustrating as that stopped work for the day. I've had a chat with Jetstream and we will be looking into it next week so interested to see how that progresses.
here are some pics of what i'm talking about...
of course the Arrow conrods are shorter than the original ford parts to lower the compression ratio for the turbos so the piston would sit lower in the cylinder which would explain why Noble would have needed to machine the pistons here.
The mountune pistons have about 1mm of extra material than the Noble pistons so it is not far off.
The Mountune pistons are designed for the normally aspirated engine so they would not be expecting the shorter conrods so i think i need to get the pistons machined in a similar way but as i say, we are looking into it and will let you lot know what we find out.
cheers
James
here's a little update on the winter rebuild. sorry i've been so quiet, busy times.
spent the last month or so cleaning up the various engine parts ready for the rebuild. in between xmas and new year i took a little trip to Jetstream to pick up all the gaskets and gear linkage parts.
I've also started to cut the tunnel ready for the Jetstream gear linkage upgrade and wiring in my data logger.
I was planning on getting the original pistons cleaned up and ceramic coated but when tracksport were cleaning the ring grooves one of the pistons broke apart. this explains the pressure that was getting into the sump when i was at Silverstone.
here's a pic of the bit that broke off. it was the only piston which was damaged
the heads are back from the engine builder. They were leak tested and checked for flatness and all ok :-). the valves were ground in and the valve seals were replaced.
the exhaust has just come back from CamCoat and looks the business.
Andy from Tracksport travelled up yesterday to help me get the engine back together. We honed the bores and put the new Mountune forged pistons, arrow conrods and uprated new bearing shells together.
we then hit a bit of a snag. we fitted a couple of the pistons to the block and turned the engine by hand to make sure everything was ok and when the pistons got to the bottom of the stroke the engine would not turn further. on further inspection we could see the bottom of the new pistons was contacting the counter weight on the crank (on both pistons we had fitted).
We then compared the new pistons to the original Noble ones and the original ones are cast pistons but then someone has machined away material around the gudgeon pin to prevent this clash. Frustrating as that stopped work for the day. I've had a chat with Jetstream and we will be looking into it next week so interested to see how that progresses.
here are some pics of what i'm talking about...
of course the Arrow conrods are shorter than the original ford parts to lower the compression ratio for the turbos so the piston would sit lower in the cylinder which would explain why Noble would have needed to machine the pistons here.
The mountune pistons have about 1mm of extra material than the Noble pistons so it is not far off.
The Mountune pistons are designed for the normally aspirated engine so they would not be expecting the shorter conrods so i think i need to get the pistons machined in a similar way but as i say, we are looking into it and will let you lot know what we find out.
cheers
James
When I had my after market forged pistons made, I had the same issue. They coppied the std pistons but made the skirts longer than std do they were. Dry close to the crank. Had to shave off a 1mm. Luckily it kept them within the tolerances allowed for when the whole system was balanced.
been speaking to Dave at Jetstream today, very helpful.
he's spoken to Mountune and they don't think they have every machined pistons but we doubt that. Dave has another set of pistons, rods and a crank and his has the same clash.
we both plan to machine the back of the pistons to remove the clash. will put some pics up soon. it only needs a small area reducing by just over 1mm.
here are some pics of my sexy black ceramic coated exhasut. the exhaust was bead blasted prior to coating and has come up really well.
he's spoken to Mountune and they don't think they have every machined pistons but we doubt that. Dave has another set of pistons, rods and a crank and his has the same clash.
we both plan to machine the back of the pistons to remove the clash. will put some pics up soon. it only needs a small area reducing by just over 1mm.
here are some pics of my sexy black ceramic coated exhasut. the exhaust was bead blasted prior to coating and has come up really well.
Jamescmr2 said:
been speaking to Dave at Jetstream today, very helpful.
he's spoken to Mountune and they don't think they have every machined pistons but we doubt that. Dave has another set of pistons, rods and a crank and his has the same clash.
we both plan to machine the back of the pistons to remove the clash. will put some pics up soon. it only needs a small area reducing by just over 1mm.
I guess those will be mine then. he's spoken to Mountune and they don't think they have every machined pistons but we doubt that. Dave has another set of pistons, rods and a crank and his has the same clash.
we both plan to machine the back of the pistons to remove the clash. will put some pics up soon. it only needs a small area reducing by just over 1mm.
I thought the Mountune forged pistons were a common upgrade and should just work straight out of the box!
daddysumo said:
James,
1) Are you using the Noble Arrow rods or Mountune Arrow rods.
2) Are you uing M400 type pistons or Mountune spec pistons.
Keep up the good work.. looking good !
hey Steve,1) Are you using the Noble Arrow rods or Mountune Arrow rods.
2) Are you uing M400 type pistons or Mountune spec pistons.
Keep up the good work.. looking good !
just seen your post. Noble Arrow rods and i'm 99% sure the pistons are Mountune spec as the M400 ones don't fit the Arrow rods (from what i understand).
On another note, the pro alloy header tank arrived today from Jetstream and it looks bloody good, well made bit of kit.
Also, the Pistons have been sent back to Jetstream where they will be machined. thanks to them for sorting a fix and picking up the cost of modifying them.
Planning on rebuilding the engine on Sat 4th of Feb as away for the next two weekends.
cheers
James
had a great day yesterday...
rebuilt the engine with Andy from AW Tracksport keeping a careful eye on my workmanship. went smoothly.
going to pop in the garage for a couple of hours this afternoon and pop the turbos on and get the exhaust fitted one night this week. all getting exciting now. no reason why i shouldn't be done by my target, end of Feb :-). the Spa/Ring trip in April is looking more likely...
couple of black head gaskets ;-)
cheers
rebuilt the engine with Andy from AW Tracksport keeping a careful eye on my workmanship. went smoothly.
going to pop in the garage for a couple of hours this afternoon and pop the turbos on and get the exhaust fitted one night this week. all getting exciting now. no reason why i shouldn't be done by my target, end of Feb :-). the Spa/Ring trip in April is looking more likely...
couple of black head gaskets ;-)
cheers
Jamescmr2 said:
had a great day yesterday...
rebuilt the engine with Andy from AW Tracksport keeping a careful eye on my workmanship. went smoothly.
going to pop in the garage for a couple of hours this afternoon and pop the turbos on and get the exhaust fitted one night this week. all getting exciting now. no reason why i shouldn't be done by my target, end of Feb :-). the Spa/Ring trip in April is looking more likely...
couple of black head gaskets ;-)
cheers
Should not one of those be blue........rebuilt the engine with Andy from AW Tracksport keeping a careful eye on my workmanship. went smoothly.
going to pop in the garage for a couple of hours this afternoon and pop the turbos on and get the exhaust fitted one night this week. all getting exciting now. no reason why i shouldn't be done by my target, end of Feb :-). the Spa/Ring trip in April is looking more likely...
couple of black head gaskets ;-)
cheers
a few more pics uploaded...
made a bit more progress on Monday night after work :-)
a pic of when i was first stripping the car apart... all over the drive
look what some kind garage left in the car!!!! no word of a lie, when i routing some cables for the data logger i pulled away the aircon pipes and found a ratchet spanner behind them!!! thanks to whichever garage donated that to me...
front turbo in place with ceramic coated header and down pipe/cat
front head shield and dip stick in place...
getting there. started looking at routings of harnesses etc.
hoping to finish all bar the finishing touches off this weekend. will take some pics of the upgraded gear linkage as well. i have it all bolted in place and it changes well. i still need to do a little bit of adjustment and then make the cover for the tunnel...
celebrated the progress last weekend by booking onto the trackday on Sat 17th March (Silverstone GP) and Spa on 2nd April :-)
cheers
James
made a bit more progress on Monday night after work :-)
a pic of when i was first stripping the car apart... all over the drive
look what some kind garage left in the car!!!! no word of a lie, when i routing some cables for the data logger i pulled away the aircon pipes and found a ratchet spanner behind them!!! thanks to whichever garage donated that to me...
front turbo in place with ceramic coated header and down pipe/cat
front head shield and dip stick in place...
getting there. started looking at routings of harnesses etc.
hoping to finish all bar the finishing touches off this weekend. will take some pics of the upgraded gear linkage as well. i have it all bolted in place and it changes well. i still need to do a little bit of adjustment and then make the cover for the tunnel...
celebrated the progress last weekend by booking onto the trackday on Sat 17th March (Silverstone GP) and Spa on 2nd April :-)
cheers
James
Hollowpockets said:
andygtt said:
impressive... your also a snowboarder 
Where do you guys go boarding down there? Think I'm off to glenshee on Sunday to practice some rails and jumps. 
andygtt said:
got back from meribel a week or so ago, there was 15 of us all boarding and even Tuxmans brother came... Tux himself didnt as apparently he is too old and frail to do things like that now
Cool, I was in Val Thorens the last week of January, had a 3 valley pass so spent a couple of days in Meribel and Courchevel dodging trees. amazing place!Gassing Station | Noble | Top of Page | What's New | My Stuff