Need a machinest opinion QUICKLY!

[LKWTSI]

Hey there. Here's the thing. I already have a engine shop telling me I'm screwed and need to use my old block, but I want some second opinions before I throw out another couple hundred on machine work.

I bought this block to replace my old one after the TBelt stripped and bent a bunch of stuff. Long story short this was supposed to be a straight swap for my old engine. I decided to do some extra work on the new one before dropping it in and I pulled the head and found this nick on the cylinder.

I've tried to explain in the pic', what I'm getting at, but I need to know if anyone else thinks this block is scrap!! My engine guy tells me it looks like the block has been decked to get rid of the nick as best they could and I fear the same thing.

After putting the piston at TDC the top of the piston is within thousandths of the top and for the best part of it I'd say flush. The lines in the picture explain where the top lip of the piston is in relation to the cylinder and the other line shows where the piston piston is in relation to the block surface. I hope this makes sense.

My concern is that when the gasket is laid down on the block there's still a tiny gap that is between the piston and the cylinder. We've both concluded that this will cause a route for gases to burn through the head gasket eventually.

WHAT DO YOU GUYS THINK

 

[GSXSixteenG]

You will be fine. The head gasket will go to the edge of where it starts to taper. It will barely overlap the nick, from the pictures it doesn't even look like that deep of a nick. If your scared go with a metal head gasket rather than a composite.

 

[LKWTSI]

here's a pic I took on my phone as my camera is dead right now. Hope this helps a little.

The yellow circle is where the nick is and the white check is about where the nick is located and isn't as deep as the white shows, but I wanted to make sure you could see about where it was.

Sorry about the quality of the pic.

 

[Street Surgeon]

I'm not a machinist, but I'd get a new block.

 

[LKWTSI]

I'm not a machinist, but I'd get a new block.

I appreciate your concern and I actually have another block...the old one that I took out after my belt broke. I'm trying to see if I can get away with this nick or not, before I go and spend another couple of hundred bucks getting the old block machined.

 

[Zex4g63]

As long as the nick does not go under the gasket it will be fine. If the nick goes under the headgasket it will burn it and blow it right there.

 

[LKWTSI]

As long as the nick does not go under the gasket it will be fine. If the nick goes under the headgasket it will burn it and blow it right there.

I have to put the gasket back on and check but I'm fairly sure the nick did go under the gasket I'll try and take a picture tomorrow.

 

[lq1driver]

tell me what you think of the scratches in cylinder 2

 

[LKWTSI]

tell me what you think of the scratches in cylinder 2

Kind of hard to see, but from my understanding, as long as you can't actually feel the scratches, you should be alright. If you can run you fingernail across them and feel them then you most likely need at the minimum a good honing job and at the worst a bore job to cut the scratches out.

I am about to scrap this block and send my original block to the shop to get worked over and start this rebuild from scratch. The guy I bought this semi complete engine from said the machine shop did all the work and from what I can see they tried to hide all sorts of crap work. I think this block had a piston go out and they decked the block to the limit and still couldn't get the nick out. They put it back and tried to call it good. From what I can see they did a great hack job and I fortunately found out before I rebuilt it and ran it and ended up blowing a gasket or worse.

Here's a pic of the scratches in my cylinder and see if they are as bad as yours. In my opinion the scratches won't hurt unless they are deep and are being caused by something more than just normal wear and tear.

 

[lq1driver]

my scratches can just barely be felt with a finger nail i am just super anal. but i am on a budget and if i have to take a trip to the machine shop its going to put my over budget and i wont be able to finish the car. ive had alot of people tell me not to worry about it. but all those people dont have to take the loss if this engine burns oil or looses compression.im going to try to make time to make it to the machine shop this week to see what the machinist thinks

 

[dented_coffee]

in my years of rebuilding the 4g's i have never ran into this problem. the notch that as taken out of the upper portion of the deck was probably caused by a broken valve that was clanking arround in there possible caused by broken timing belt. the notch will cause your gasket to see extreme heatand blow out in that area. in most cases.

the deck is milled to the limit right. are you shure. is there a way you can obtain the paperwork from the shop that did the block works on it.

 

[LKWTSI]

in my years of rebuilding the 4g's i have never ran into this problem. the notch that as taken out of the upper portion of the deck was probably caused by a broken valve that was clanking arround in there possible caused by broken timing belt. the notch will cause your gasket to see extreme heatand blow out in that area. in most cases.

the deck is milled to the limit right. are you shure. is there a way you can obtain the paperwork from the shop that did the block works on it.

No, I wish there was, but the run around I'm getting from the guy, that I bought the engine from leads me to believe I won't be seeing any help on this.

The engine shop, I'm using just now, figures it already has been done just by the surface finish. I don't know for sure the dimensions for the block height, so I can't tell for sure. Does anyone know what or where I can get the block to deck height measurement and what tolerances there are for this.

 

[pj91gsx]

i would file it smooth, just because it can become a hot spot. It may be ok if you dont file it, but its good to keep it from having edges.

 

[LKWTSI]

Here's a couple of pic's with the gasket in place. You can see pretty clearly the gap that is created and I'm just about ready to call it quits on this block and send my old one into the shop and get it done right and scrap this one.

 

[Zex4g63]

Does it go under the gasket or end at the gasket?

 

[dented_coffee]

it looks ok to use imoa now that we can officially see a gasket pinch ring in place. like pj said file it. dont go crazy with the file just remove the edge off of it to make it less of a pocket. the rings dont go up that far so you should be good to go. save some time money and hassle. get that dsm on the road where it belongs.

 

[firefighter]

Its fine. Just run it.Some times you screw around with it trying to file it you'll end up making it worst. When I got my eclipse It had burnt rings in number one cylinder (peices of it were gone) the cylinder had some deep scratches in it. I honed the cylinder the best I could .I removed about 90% of it. If you took your finger nail and scratched the surface you could bearly feel it( I was afraid of making the cylinder not true the length of the bore). Put the engine back together and ran it, so far I put five thousand miles on it with no problems. Bye the way you are looking at deck height. You measure from the top of the pistons at TDC to the top of the block Make sure you are using the height of the stock pistons to get the measurement.Get in touch with the dealership or go on the net to get the stock deck height.Subtract the number you get,from the OEM deck height that will be how much has been removed.To drive you a little more crazy depending on how much has been removed you could change the compression ratio.

 

[LKWTSI]

Its fine. Just run it.Some times you screw around with it trying to file it you'll end up making it worst. When I got my eclipse It had burnt rings in number one cylinder (peices of it were gone) the cylinder had some deep scratches in it. I honed the cylinder the best I could .I removed about 90% of it. If you took your finger nail and scratched the surface you could bearly feel it( I was afraid of making the cylinder not true the length of the bore). Put the engine back together and ran it, so far I put five thousand miles on it with no problems. Bye the way you are looking at deck height. You measure from the top of the pistons at TDC to the top of the block Make sure you are using the height of the stock pistons to get the measurement.Get in touch with the dealership or go on the net to get the stock deck height.Subtract the number you get,from the OEM deck height that will be how much has been removed.To drive you a little more crazy depending on how much has been removed you could change the compression ratio.

Thanks for the info guys. Yeah I'm at the opinion right now that I'll polish out the nick and go for. I'm going over budget as it is, but I'm wanting this thing running soon.
Will let you know as I get the thing back running.

 

[GSXSixteenG]

It does look deeper than I originally thought. But as I said before, I didn't think it would go under the gasket. Smooth it out and go.

 

[Blackjet18t]

I've actually seen many make reliefs where that nick is. What they do it sorta grind either side of the cylinder. It "supposed" to ease the airflow in and out. I have worked in machine shops and done my own engines. The only one I've seen it done on were small blocks both ford and chevy.

 

[black_gst]

Looks like it could cause some problems IMO, since it appears that it goes under the fire ring

 

[black_gst]

what about using an over sized HG would +.040 get you past that nick?

 

[LKWTSI]

what about using an over sized HG would +.040 get you past that nick?

I don't know It's already 0.020 overbored as it is. I don't know if that would help or not. I'm going to talk with my machine shop guy and get his opinion again and see if he really thinks I can get away with it or not. I think I'm going to go with getting my other block done and be 100% sure I'm not going to taer this down again in a couple of months due to a blown head gasket.

 

[EclipticalGS]

Im a nitpick and I wouldnt use it. Thats a week spot now.

 

[Zex4g63]

I've actually seen many make reliefs where that nick is. What they do it sorta grind either side of the cylinder. It "supposed" to ease the airflow in and out. I have worked in machine shops and done my own engines. The only one I've seen it done on were small blocks both ford and chevy.

Yes we do that to super stock and stock eliminator engines but the gasket is also shaped to go around the relief. If the bottom of the gasket is exposed to flame it will burn thru.

what about using an over sized HG would +.040 get you past that nick?

Get a MLS gasket with a larger bore. Then it would be fine.