Piston size!
- Jens Hansen
- 356 Fan
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- Location: Droitwich, Worcestershire
Piston size!
Several years ago my dad and I bought a T5. Think it was on the road somewhere in the states in the mid seventies but not sure.
2 years ago my dad started the body work and hopefully he will finish it soon.
The engine was inside the car when we bought it.
Engine number is: 71787, 1600cc, 616/1 for a T2 1959.
Yesterday evening I got a few things done but I don't know how to see the piston size!
On 1 of the pistons the is "3" stamped and on 3 of the other cylinders there is "2" stamped on each of them.
The cylinders are rusted on the outside but inside they are perfect.
How can I tell what size the pistons are?
Hope someone can help me!
Thanks,
Jens
2 years ago my dad started the body work and hopefully he will finish it soon.
The engine was inside the car when we bought it.
Engine number is: 71787, 1600cc, 616/1 for a T2 1959.
Yesterday evening I got a few things done but I don't know how to see the piston size!
On 1 of the pistons the is "3" stamped and on 3 of the other cylinders there is "2" stamped on each of them.
The cylinders are rusted on the outside but inside they are perfect.
How can I tell what size the pistons are?
Hope someone can help me!
Thanks,
Jens
Jens Hansen
1962 T6 Coupe S90
1960 T5 Coupe Normal
1960 Morris Minor Conv.
1962 T6 Coupe S90
1960 T5 Coupe Normal
1960 Morris Minor Conv.
-
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Re: Piston size!
You say you can see the inside of the cylinders. So, why not measure the bore diameter and then you'll know.
- Jacques Lefriant
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Re: Piston size!
that vintage sizes were -1,0,+1 heights were 5,6, usually. you may have to actually measure them with a micrometer and bore gauge.
j
j
- Jens Hansen
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- Location: Droitwich, Worcestershire
Re: Piston size!
Diameter is 86mm! It's the number on the piston I can't find anywhere. Might have to look at the maestro's book again.
Jens Hansen
1962 T6 Coupe S90
1960 T5 Coupe Normal
1960 Morris Minor Conv.
1962 T6 Coupe S90
1960 T5 Coupe Normal
1960 Morris Minor Conv.
- C J Murray
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Re: Piston size!
That is an aftermarket replacement piston and cylinder.
Regardless of what pistons and cylinders you might have you should measure the bore for size, roundness, and taper and then measure the piston to calculate clearance. The piston rings should get a visual check and measure the gaps. Any markings on used parts are meaningless.
Regardless of what pistons and cylinders you might have you should measure the bore for size, roundness, and taper and then measure the piston to calculate clearance. The piston rings should get a visual check and measure the gaps. Any markings on used parts are meaningless.
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- Jens Hansen
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Re: Piston size!
I'll get some new piston rings after I have checked the cylinders and pistons.
Thanks for the replies.
Thanks for the replies.
Jens Hansen
1962 T6 Coupe S90
1960 T5 Coupe Normal
1960 Morris Minor Conv.
1962 T6 Coupe S90
1960 T5 Coupe Normal
1960 Morris Minor Conv.
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Re: Piston size!
Jen,
If the pistons are OEM Mahle, you should see some stampings on top of the pistons like 82,45 (for 1600cc);
If the stamping is 83,0, it's a 1st oversize, and going further, there's a 2nd oversize; Big bore sets are 85 and 86mm
Also, piston ring gaps should be in the range per the spec book (or shop manual) including the wear limit of the side clearance to the groves.
Finally, there's a difference of piston clearances w/aluminum vs. cast iron cyl's.; Full alum. are 'things of the past".
Late Biral cyls. are similar to cast iron w/cast aluminum fins and full CI cyls. should be matched heights w/in .0004"!
Dick
If the pistons are OEM Mahle, you should see some stampings on top of the pistons like 82,45 (for 1600cc);
If the stamping is 83,0, it's a 1st oversize, and going further, there's a 2nd oversize; Big bore sets are 85 and 86mm
Also, piston ring gaps should be in the range per the spec book (or shop manual) including the wear limit of the side clearance to the groves.
Finally, there's a difference of piston clearances w/aluminum vs. cast iron cyl's.; Full alum. are 'things of the past".
Late Biral cyls. are similar to cast iron w/cast aluminum fins and full CI cyls. should be matched heights w/in .0004"!
Dick
- Wil Mittelbach
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Re: Piston size!
Additionally; ensure that the piston ring lands/grooves are not worn beyond ring/land clearance specs to assure a proper ring/piston fitment.Jens Hansen wrote:I'll get some new piston rings after I have checked the cylinders and pistons.
Thanks for the replies.
- Jens Hansen
- 356 Fan
- Posts: 133
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- Location: Droitwich, Worcestershire
Re: Piston size!
Just to be sure then I'll get a new set of cylinders and pistons.
Thanks for the help.
Thanks for the help.
Jens Hansen
1962 T6 Coupe S90
1960 T5 Coupe Normal
1960 Morris Minor Conv.
1962 T6 Coupe S90
1960 T5 Coupe Normal
1960 Morris Minor Conv.
- Jens Hansen
- 356 Fan
- Posts: 133
- Joined: Sat Jun 06, 2009 5:54 am
- Location: Droitwich, Worcestershire
Re: Piston size!
In the process of installing the piston rings. On the 3rd ring there's a spring.
Should I change that spring at the same time as I install new piston rings or should/can I leave the old spring?
Better be sure to do it right the first time.
Thanks in advance
Jens
Should I change that spring at the same time as I install new piston rings or should/can I leave the old spring?
Better be sure to do it right the first time.
Thanks in advance
Jens
Jens Hansen
1962 T6 Coupe S90
1960 T5 Coupe Normal
1960 Morris Minor Conv.
1962 T6 Coupe S90
1960 T5 Coupe Normal
1960 Morris Minor Conv.
- C J Murray
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Re: Piston size!
Some oil rings have springs and some do not, depends on design. If the rings are a new set they should be complete to replace all the parts of the old ring set.
You had better post detailed pictures of what you have.
You had better post detailed pictures of what you have.
'57 Speedster
'59 Sunroof
'60 Devin D Porsche Race Car
'63 Cabriolet "Norm"
'67 911 S Original Owner
'03 Ferrari 575M
'09 Smart Passion
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'60 Devin D Porsche Race Car
'63 Cabriolet "Norm"
'67 911 S Original Owner
'03 Ferrari 575M
'09 Smart Passion
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Re: Piston size!
cheers
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- Jim Nelson
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Re: Piston size!
There's also an early Kolbenschmidt big bore kit, 85.45mm, that is for non-counterbalanced cranks. Works out to a little over 1697cc.
- Ron LaDow
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Re: Piston size!
Pretty sure that was the "industrial" PC set; flat topped, you're be hard put to get more than 7.5:1 out of them.jim nelson wrote:There's also an early Kolbenschmidt big bore kit, 85.45mm, that is for non-counterbalanced cranks. Works out to a little over 1697cc.
Ron LaDow
www.precisionmatters.biz
www.precisionmatters.biz
- Jim Nelson
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Re: Piston size!
Beats me, Ron, there isn't a lot of documentation with the box.Ron LaDow wrote:Pretty sure that was the "industrial" PC set; flat topped, you're be hard put to get more than 7.5:1 out of them.jim nelson wrote:There's also an early Kolbenschmidt big bore kit, 85.45mm, that is for non-counterbalanced cranks. Works out to a little over 1697cc.