Gasket thickness is the easiest way out, if that's not an option for whatever reason then its machine the piston height, and or put value pockets in the piston.
In these cases, when you have holes in the surface where you want to put the magnetic base, I normaly stick it to a calibrated (grinded) base plate and so I can slide it all over the surface wehere I need to take measurements.
I just got my 2.0 BHW head and block back from the machine shops yesterday, and they took .015 off the top that I will "add" to my piston protrusion height. I'm nervous, this is my first build. Thanks for the helpful explanations.
Phew" I'm glad I just watched that" when I did the valves on 1.8d feista, I noticed the head had been skimmed" so I put a 4 noch gasket rather than a 2" now I know I choose right ) thank for the heads up on the pump )) I'll send a vidio a bit later... your really amazing & I'm sure everyone is glued to your channel.. cheers
The Vauxhall Cavalier mk2 engine was non-interference engine, was great if the timing belt went you could fix it on side of the road and be back running in under an hour. Also the clutch could be done in 45mins without the gearbox being removed, thanks to an inspection panel. People often wondered why they done away with it, should be obvious more clutches were changed in lunch hours than work hours ;) lol.
Had similar marks on the piston from valve strikes. 300TDI. Broken rockers and bendy push rods. The valve stem caps were also donuting them selves way to often. Turns out the cam shaft pin that ties into the camshaft gear had ovaled out it's hole in the cam shaft. Took forever to track that down as the issue because it's buried in the timing cover.
good theory on shims......my only thoughts on this are if the the gasket is bespoke ...you will need to make two......for a spare...if the fueling is turned up.....he may need three spares😆
@@davidbrodie5044 to be honest I doubt machining the pistons in this engine would have any ill effect but of course it is a chunk of work to get them out
If you are considering either a bespoke gasket or machining pistons I'd choose the pistons tbh. Common practice for engine builders to machine valve relief in piston crowns to accommodate either bigger valves or higher lift cams. Obviously you measure the crown thickness before you commit. Re: measuring piston protrusion. I would get JP to take a piece of rectangle bar stock and drill a hole for the dial gauge and a rebate to clear above the piston as an alternative to a mag base.
i followed your comments when i did my head and it actually only needed a 2 hole not the 3 hole it had even after having the head skimmed then used the 2.8 torque rules
I had a belt let go on a FIAT twin cam at around 6000 rpm. The engine was toast. I sent you a pic of my 300TDi where the tensioner stud broke. That one broke 3 rockers and bent all 8 pushrods.
The new TBelt kits they're selling here in Australia now include a new replacement stud for the tensioner, they say replace it regardless of if it looks ok, usually the old ones get fatigued. Mate of mine had his go on a TDI engine he'd just re timing belted, thought the old stud was ok. No bent valves though, God bless the old TDI, just the new stud, a few push rods and a couple of rockers and on his way, legend!
I like the thick gasket idea(Put another hole in it to give next person in there a clue!). Skimming the piston might do strange things to the compression ratio as well as reducing reliability. Would skimming the valves be an option? Quite cheap to do on a lathe, I would have thought.
You should have kept the 1275 head and fitted it with double valve springs. The valves don't bounce then. I used to have a 1071S engine, and that used to REV!!!!!!!!!!!!
Mike, if I had run out of options because someone had decked the block too far, I'd check the piston protrusions, then proceed as per correction of oval big end bearing bores, except instead of the cap faces I'd skim the rod side faces of the rod/cap mating surfaces by the required excess protrusion dimension then resize the big end bearing bores. Same stroke just a little lower from the top and within spec for the head gasket thickness spec. As said only as a last resort to keep the block.
@@BritannicaRestorations I think cheaper than replacing a block, and the only other suitable option is to machine piston crowns, which with the TDI maybe no option at all. To resize the rod ends is a fairly routine operation for an engine reco shop, just done in a lathe or on a universal mill with fly cutter then hone, they do it all the time to save rods where bearings shells have spun. I'd certainly do it to save an otherwise perfect block, no biggie.
Very interesting about the custom gasket idea ! Unlike a lot of engines there’s no seal ring round the bore on the 300tdi head gasket so I can’t see why a custom gasket can’t be made. Gotta be careful skimming pistons , fine providing they’re all balanced but like you say a lot of work.
Would a 3 hole gasket be detrimental on a head and block that's not been skimmed or only lightly skimmed ? I'm guessing the difference in compression would be negligible. What I mean is, does it hurt to go to the thickest gasket even if the piston petrusion says 1 hole or 2 hole .? Peace and love brother 👍🏻☮❤
I am imagining a future UA-camr in twenty years time with a real mystery. He has a 300tdi engine where the owner has replaced the head gasket and now it's knocking? It's the correct gasket and the old gasket looked standard. A real Miss Marples type of mystery.
Once you have a reference measure for your piston heights you can measure the the Azerbaijan and calculate how much has been machined off, is it not possible to skim some more off the block to compensate for 2 stock gaskets to achieve the correct clearance and compression ratio and leave the pistons and bottom end alone, bad idea to skim pistons it will put it out of balance . If you put two shims in you will also have to some gasket material between the shims I don't think it's practible.
yep sounds good, my only concern is the accuracy of non calibrated digital vernier gauges might be a good idea too check them against engineers slip gauges for that precise a job
@@BritannicaRestorations Only problem with theory was told to me when at college for motor vehicle engineering. "The course is split into two parts, theory and practical, 30 percent theory and 70 percent practical. As theory is fine but rarely works in practice lol." In saying that I hope it works, it sounds a great solution.
You can run a 13 head on an 1100 if you pocket the block i use to race minis 1300 head was a cheap big valve job sometimes i just can't afford a 1275 motor so Austin 1100 had to do Another way to measure it get ablock of steel 2inch by 4 by1 thick get jp to mill a step 1/8 half way across the long face tben drill a hole to take your dti with a thumb screw to hold it 0 it ona flat surface that won't rock
Ahh nostalgia - cheers! Allegro 1300 heads bolted straight on and had enough meat to take them out to 1340 - loadsa fun. Take out the clock to let the twin Webber trumpets through the bulkhead and you could smoke V8 Jags and Xr3's up the bypass all day long. I can still hear those Webbers sucking lungfuls as the A-series redlined in 3rd.. Halcyon days - sweet 👍
Whats with the figures on the tightning sequence mike. I have recently done mine. I think it said 40nm plus 60 degrees and 60 degrees followed by 20 degrees on inner cylinder head bolts
I Like the way you think, simply can't see a problem with a mix and match head gasket, well worth a punt. Nothing ventured and all that. Skimming the pistons would be a lot of work, there is also the combustion chamber in the piston which would also need to be corrected after it was skimmed, each would have to be returned to its designed volume which would make balancing them quite a lot of mucking about. Would the reduction in the volume cause problems for a compression detonation engine? Can a diesel pre detonate? Lovin this problem Mike
If the block was too far skimmed - then returning it to the original STD should not cause issues Needs the head off to see what is going on and measuring up - I should be able to work out the gasket thickness from measuring the protrusion of the pistons as they are and adding shims in the gasket to make it 0.50 to 0.60 mm minimum
Is the top of the piston actually hitting the head? Would be another question. If not, why not drop the valves a little further into the head? Maybe the the mechanic didn't do that when assembling the thing? Just a thought.
It sounds a good idea mike but if there is one piston that is over protruding either due to a rod/piston issue or the block decking issue. If you space the head gasket enough to sort the clearance for that one piston what is the compression going to be like on the others if they are correct? I know diesels of this age aren't that fussy, but depending what you find we could be talking fairly different CR's from the front of the block to the back - of course if you get in there and the whole thing has been Skimmed on the piss not once but twice, that would at least explain things. Although it leaves you looking for another engine again.
Could also put valve pockets in the piston crowns or indeed skim the tops off, I think a dodgey thicker gasket would be sketchy. Or sink the valve seats which is what we used to do on the cosworths after facing the heads/blocks.
I've used 3 hole gasket on 200tdi engines with no noticeable performance or reliability degradation. A mate overheated a 300tdi D1. We got the head skimmed and the engineer went to the max allowed but still didn't get it completely flat. My mate was like sod it, so we put the 3 hole gasket on. Pulled the lock pins and turned the engine manually twice over with no contact. And sure enough the loyal tdi fired up and ran well enough. Guess God looks after fools and drunk cos we hadn't been drinking haha
I would be to have the pistons turned down, adding an extra shim could fail as the layer arrangement would be wrong, ie soft hard hard soft instead of soft hard soft, it means you have no soft sealing material between the two central layers, but if you do it make a vid to show it works, ps how much trouble has this engine been to need two block skims, interesting
Given the choice I would machine the pistons. Those digital calipers should only be used as an approximation, especially the cheap ones, infact don't buy the cheap one, buy a second hand depth mic instead.
@@BritannicaRestorations it was a general statement not an accusation Mike. I use exactly the same one but most people seem to think the Aldi version is the Same. But, where I can I prefer to use a micrometer. You don't see the digital calipers used in good tool rooms..
Gasket thickness is the easiest way out, if that's not an option for whatever reason then its machine the piston height, and or put value pockets in the piston.
In these cases, when you have holes in the surface where you want to put the magnetic base, I normaly stick it to a calibrated (grinded) base plate and so I can slide it all over the surface wehere I need to take measurements.
Good idea!
I just got my 2.0 BHW head and block back from the machine shops yesterday, and they took .015 off the top that I will "add" to my piston protrusion height. I'm nervous, this is my first build. Thanks for the helpful explanations.
Good stuff
Great video - compression ratio will also be affected which can make an engine knocky if its too high - detonation time
Phew" I'm glad I just watched that" when I did the valves on 1.8d feista, I noticed the head had been skimmed" so I put a 4 noch gasket rather than a 2" now I know I choose right ) thank for the heads up on the pump )) I'll send a vidio a bit later... your really amazing & I'm sure everyone is glued to your channel.. cheers
The Vauxhall Cavalier mk2 engine was non-interference engine, was great if the timing belt went you could fix it on side of the road and be back running in under an hour. Also the clutch could be done in 45mins without the gearbox being removed, thanks to an inspection panel. People often wondered why they done away with it, should be obvious more clutches were changed in lunch hours than work hours ;) lol.
Great point!
Best engine and box they ever made I had the 1,8 Sri and a 1.6 sr for the wife Great cars
What a good idea to combine two head gaskets. 😉
Cheers to King Mike. 🥃
Thanks 👍
Had similar marks on the piston from valve strikes. 300TDI. Broken rockers and bendy push rods. The valve stem caps were also donuting them selves way to often. Turns out the cam shaft pin that ties into the camshaft gear had ovaled out it's hole in the cam shaft. Took forever to track that down as the issue because it's buried in the timing cover.
That's very rare!
good theory on shims......my only thoughts on this are if the the gasket is bespoke ...you will need to make two......for a spare...if the fueling is turned up.....he may need three spares😆
In performance engines it is amazing how much people machine the piston crowns, not just for deck height but also for valve clearance.
Yes I've seen that done with Cosworths, a few thou off the crown. Jobs a goodun and no prob with a custom gasket in the future.
@@davidbrodie5044 to be honest I doubt machining the pistons in this engine would have any ill effect but of course it is a chunk of work to get them out
If you are considering either a bespoke gasket or machining pistons I'd choose the pistons tbh. Common practice for engine builders to machine valve relief in piston crowns to accommodate either bigger valves or higher lift cams. Obviously you measure the crown thickness before you commit.
Re: measuring piston protrusion. I would get JP to take a piece of rectangle bar stock and drill a hole for the dial gauge and a rebate to clear above the piston as an alternative to a mag base.
Let's see, when the head is off!
ua-cam.com/video/S9fvxhX-QRQ/v-deo.html
This exactly the homemade tool I was referring too.
Good idea all round.
Glad you think so!
i followed your comments when i did my head and it actually only needed a 2 hole not the 3 hole it had even after having the head skimmed then used the 2.8 torque rules
Great video, again Mike!
Glad you enjoyed it!
I had a belt let go on a FIAT twin cam at around 6000 rpm. The engine was toast.
I sent you a pic of my 300TDi where the tensioner stud broke. That one broke 3 rockers and bent all 8 pushrods.
The new TBelt kits they're selling here in Australia now include a new replacement stud for the tensioner, they say replace it regardless of if it looks ok, usually the old ones get fatigued. Mate of mine had his go on a TDI engine he'd just re timing belted, thought the old stud was ok. No bent valves though, God bless the old TDI, just the new stud, a few push rods and a couple of rockers and on his way, legend!
I had a belt let go on a Honda EB2 Civic, went to town and got another belt, put it on and was away again.
I like the thick gasket idea(Put another hole in it to give next person in there a clue!). Skimming the piston might do strange things to the compression ratio as well as reducing reliability. Would skimming the valves be an option? Quite cheap to do on a lathe, I would have thought.
As this is a new head, I do not think it needs touching - but we will only find out when the head is off!
You should have kept the 1275 head and fitted it with double valve springs. The valves don't bounce then. I used to have a 1071S engine, and that used to REV!!!!!!!!!!!!
Mike, if I had run out of options because someone had decked the block too far, I'd check the piston protrusions, then proceed as per correction of oval big end bearing bores, except instead of the cap faces I'd skim the rod side faces of the rod/cap mating surfaces by the required excess protrusion dimension then resize the big end bearing bores. Same stroke just a little lower from the top and within spec for the head gasket thickness spec. As said only as a last resort to keep the block.
I see what you are saying, but it is a fair bit of work
@@BritannicaRestorations I think cheaper than replacing a block, and the only other suitable option is to machine piston crowns, which with the TDI maybe no option at all. To resize the rod ends is a fairly routine operation for an engine reco shop, just done in a lathe or on a universal mill with fly cutter then hone, they do it all the time to save rods where bearings shells have spun. I'd certainly do it to save an otherwise perfect block, no biggie.
Very interesting about the custom gasket idea ! Unlike a lot of engines there’s no seal ring round the bore on the 300tdi head gasket so I can’t see why a custom gasket can’t be made. Gotta be careful skimming pistons , fine providing they’re all balanced but like you say a lot of work.
It could be a safe and cheap way of fixing an over machined block
I agree about the pistons
So much for retirement Mike eh lol , greetings from Hexham by the way
Are you the Hexham hockler?
@@BritannicaRestorations not yet but I’m working on it Pat
Would a 3 hole gasket be detrimental on a head and block that's not been skimmed or only lightly skimmed ? I'm guessing the difference in compression would be negligible. What I mean is, does it hurt to go to the thickest gasket even if the piston petrusion says 1 hole or 2 hole .?
Peace and love brother 👍🏻☮❤
I am imagining a future UA-camr in twenty years time with a real mystery. He has a 300tdi engine where the owner has replaced the head gasket and now it's knocking?
It's the correct gasket and the old gasket looked standard.
A real Miss Marples type of mystery.
I probably won't be around to worry about it....
Once you have a reference measure for your piston heights you can measure the the Azerbaijan and calculate how much has been machined off, is it not possible to skim some more off the block to compensate for 2 stock gaskets to achieve the correct clearance and compression ratio and leave the pistons and bottom end alone, bad idea to skim pistons it will put it out of balance . If you put two shims in you will also have to some gasket material between the shims I don't think it's practible.
Does the Bearmach gasket have an oil passage hole that would seal better on a 200Tdi?
Some of the mag bases you can go from the rear as well.
yep sounds good, my only concern is the accuracy of non calibrated digital vernier gauges might be a good idea too check them against engineers slip gauges for that precise a job
I do not think it is that much of an issue - my Mitutoyo is pretty accurate and JP in the machine shop uses them all the time
A two holer vs a three holer sounds like a plumbing problem!
Seriously, sounds like the hybrid gasket could work and save a heap of machining.
Well in theory it shod work - depends on what we find with the head off
@@BritannicaRestorations Only problem with theory was told to me when at college for motor vehicle engineering. "The course is split into two parts, theory and practical, 30 percent theory and 70 percent practical. As theory is fine but rarely works in practice lol." In saying that I hope it works, it sounds a great solution.
You can run a 13 head on an 1100 if you pocket the block i use to race minis 1300 head was a cheap big valve job sometimes i just can't afford a 1275 motor so Austin 1100 had to do
Another way to measure it get ablock of steel 2inch by 4 by1 thick get jp to mill a step 1/8 half way across the long face tben drill a hole to take your dti with a thumb screw to hold it 0 it ona flat surface that won't rock
I will bear it in mind for the next time, but it was 30 years ago... Lol!
@@BritannicaRestorations yer like wise
Ahh nostalgia - cheers!
Allegro 1300 heads bolted straight on and had enough meat to take them out to 1340 - loadsa fun.
Take out the clock to let the twin Webber trumpets through the bulkhead and you could smoke V8 Jags and Xr3's up the bypass all day long.
I can still hear those Webbers sucking lungfuls as the A-series redlined in 3rd.. Halcyon days - sweet 👍
Whats with the figures on the tightning sequence mike. I have recently done mine. I think it said 40nm plus 60 degrees and 60 degrees followed by 20 degrees on inner cylinder head bolts
With the MLS gaskets as fitted to the HS 2.8, I use their set-up = much simpler. Never had a head gasket go again
I Like the way you think, simply can't see a problem with a mix and match head gasket, well worth a punt. Nothing ventured and all that. Skimming the pistons would be a lot of work, there is also the combustion chamber in the piston which would also need to be corrected after it was skimmed, each would have to be returned to its designed volume which would make balancing them quite a lot of mucking about. Would the reduction in the volume cause problems for a compression detonation engine? Can a diesel pre detonate? Lovin this problem Mike
If the block was too far skimmed - then returning it to the original STD should not cause issues
Needs the head off to see what is going on and measuring up - I should be able to work out the gasket thickness from measuring the protrusion of the pistons as they are and adding shims in the gasket to make it 0.50 to 0.60 mm minimum
Is the top of the piston actually hitting the head? Would be another question. If not, why not drop the valves a little further into the head? Maybe the the mechanic didn't do that when assembling the thing? Just a thought.
I have had no idea what has been done to this motor. This is a new head, so there is no need to recess the valves
It sounds a good idea mike but if there is one piston that is over protruding either due to a rod/piston issue or the block decking issue. If you space the head gasket enough to sort the clearance for that one piston what is the compression going to be like on the others if they are correct? I know diesels of this age aren't that fussy, but depending what you find we could be talking fairly different CR's from the front of the block to the back - of course if you get in there and the whole thing has been Skimmed on the piss not once but twice, that would at least explain things. Although it leaves you looking for another engine again.
Needs the head off and a check - it cannot be far off as a 0 hole gasket is on it at the moment, and it runs (but there is a tick)
@@BritannicaRestorations As you have said you will just have to see what wonders await you!!
hi thanks for your info, as ive had the bosch ve serviced i need to reset the the fuel delivery, is their a guide for this many thanks
Not that I know of
Could also put valve pockets in the piston crowns or indeed skim the tops off, I think a dodgey thicker gasket would be sketchy. Or sink the valve seats which is what we used to do on the cosworths after facing the heads/blocks.
And then the balance of the pistons wil be out
@@BritannicaRestorations easily rectified
I know you got a better one that the rest of us , but still ,I never have trusted those digital caliper further 0.1mm .
yes , shiming gasket is better than trying to find four bent conrods which usually goes to the bin.....
a protusion Mike, eh! could be serious..? 😁
Try it. Do a compression test before instaling the motor mike
Yes I could do
Pistons for competition engines are machined all the time to set to correct piston height...
Maybe, but this is a higher compression diesel and there is no tolerance to machine pistons
I've used 3 hole gasket on 200tdi engines with no noticeable performance or reliability degradation.
A mate overheated a 300tdi D1. We got the head skimmed and the engineer went to the max allowed but still didn't get it completely flat. My mate was like sod it, so we put the 3 hole gasket on. Pulled the lock pins and turned the engine manually twice over with no contact. And sure enough the loyal tdi fired up and ran well enough.
Guess God looks after fools and drunk cos we hadn't been drinking haha
For many, 'well enough' just doesn't do it.
I would be to have the pistons turned down, adding an extra shim could fail as the layer arrangement would be wrong, ie soft hard hard soft instead of soft hard soft, it means you have no soft sealing material between the two central layers, but if you do it make a vid to show it works, ps how much trouble has this engine been to need two block skims, interesting
A tiskit a tasket what size bloody gasket!?😤
Engine shops machine piston tops all the time on blocks that have been decked.
Been done for years, sometimes it just has to be done.
Lot of work, and how does it affect the combustion chamber in the piston?
Avoid sharp edges when grinding for hot spots
Given the choice I would machine the pistons. Those digital calipers should only be used as an approximation, especially the cheap ones, infact don't buy the cheap one, buy a second hand depth mic instead.
That is a $350 certified Mitutoyo vernier - hardly a cheap Chinese one
@@BritannicaRestorations it was a general statement not an accusation Mike. I use exactly the same one but most people seem to think the Aldi version is the Same. But, where I can I prefer to use a micrometer. You don't see the digital calipers used in good tool rooms..
Its all JP uses on his lathe - and he does some pretty amazing stuff