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-   -   Cylinder bore question with pictures (https://forums.maxperformanceinc.com/forums/showthread.php?t=810749)

dammen8 10-15-2017 05:21 PM

Cylinder bore question with pictures
 
3 Attachment(s)
This is my number 4 cylinder... any idea what is going on? These marks are square with the bore, so it can't be water, you can definitely feel these marks.. the home was fresh at the beginning of this season. This is the only bore that did this.. thanks for any ideas.

Chad Dammen

johnta1 10-15-2017 09:12 PM

Are you running alcohol?

Have any head gasket problems?

Been out in the rain?

:confused:

dammen8 10-15-2017 09:25 PM

Vp x16 race fuel

No head gasket problems

No rain..

The marks are about 80% around the cylinder and square to the deck... if it was water the line would be at a angle to the deck... this is why I am confused...

slowbird 10-15-2017 09:31 PM

Engine sit for a long time without being cranked over?

Jack Gifford 10-16-2017 12:27 AM

Ring faces look any different on that cylinder?

steve25 10-16-2017 06:14 AM

Is the block filled to passed that point on the wall?

All of those vertical marks are a sure sign that at least the ends of the oil ring rails need to be rounded over , a lot of fiction getting introduced there!

dammen8 10-16-2017 06:34 AM

The longest the engine sat was 2-3 weeks if that.

Haven't pulled the pistons out yet.

The block is not filled, it's aftermarket.

dammen8 10-16-2017 06:40 AM

The ring pack is total seal classic race

.043/.043/3mm the short block turned over at 11-12 ftlbs. Well according to the cheap craftsman beam style tq wrench.

steve25 10-16-2017 07:28 AM

What has made you yank the head(s)?

If that's where the piston in 4 was sitting when you pulled the head, then it sure looks like signs of water to me, but I woukd not expect such to be showing rust pitting around 360 degrees of the Bore , only on the low side of the piston if the motor was sitting in a normal position.

You could have a leaky valve seat coolant wise?

Looking at the first shot again I see what I believe is a crack in the wall below those pit marks and just to the right of that second gas port hole.

dammen8 10-16-2017 07:52 AM

I put the heads on at the beginning of this season , they were used and needed the valve job touched up... I just didn't have time earlier to do it so I lapped the valves and ran it... also the connecting rods are only rated to 850 hp and I was way above that, so I was going to upgrade my rods as well...

I was questioning if that was a crack also.. might have to get the block pressure checked...

steve25 10-16-2017 07:59 AM

If the chamber and plug from 4 look cleaner then the others then chances are it's from water.

A crack my not open without heat, a Mag test is the way to go and far faster and cheaper!
Way above 850 hp by means of NA?

dammen8 10-16-2017 08:14 AM

It made 870 n/a and I was spraying a .026 jet in a fogger.. so 225-240 ish...

dammen8 10-16-2017 08:16 AM

All the chambers and pistons looked the same, nothing was steam cleaned...

steve25 10-16-2017 09:02 AM

Well at any rate that cylinder needs to be confirmed as good or bad at this point!

ponjohn 10-16-2017 09:29 AM

Quote:

Originally Posted by steve25 (Post 5798406)
Well at any rate that cylinder needs to be confirmed as good or bad at this point!

If needed, can that one cylinder be sleeved?

dammen8 10-16-2017 09:31 AM

Quote:

Originally Posted by steve25 (Post 5798406)
Well at any rate that cylinder needs to be confirmed as good or bad at this point!

Fully agree!

dammen8 10-16-2017 11:49 AM

Quote:

Originally Posted by ponjohn (Post 5798415)
If needed, can that one cylinder be sleeved?

I would figure that would be the fix..

lfdsteve 10-16-2017 12:56 PM

Is it a thin spot with coolant seeping in from the back side?

BruceWilkie 10-16-2017 01:56 PM

Pressure check along with a good sono of area. A sleeve should take care of it.

mysticmissle 10-16-2017 02:04 PM

total seal gapless? did it use any oil?


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