Would you run this cylinder head- in this condition-?

**Aaronhl** · 07-31-2020, 02:29 PM

Originally Posted by Merc 2.5

Yes its is a 2.5 , mine was 2.0. The 2.5 has a short skirt or notch on 1 side?. I think.? I'm not home to look ?

Yes I figured it out the 2.5 piston had a wide skirt on the exhaust side and other side notched. So might be kinda hard to put it in upside down even without UP the marking. You guys wont like it but I bought a used piston and rod (together) on ebay so going to put that in with new rings and a head gasket. Hopefully the compression is OK

**Merc 2.5** · 07-31-2020, 02:38 PM

Originally Posted by Aaronhl

Yes I figured it out the 2.5 piston had a wide skirt on the exhaust side and other side notched. So might be kinda hard to put it in upside down even without UP the marking. You guys wont like it but I bought a used piston and rod (together) on ebay so going to put that in with new rings and a head gasket. Hopefully the compression is OK

I'm all about tryin get a 150$ motor runnin for 150 or less lol. That 2.0 piston has identical skirts so had to find marking. But bad thing was I didnt think about it til I was cleanin everything so I had to clean slugs. I'll mark a 2.0 next time tho , ha

**Aaronhl** · 08-07-2020, 11:40 AM

Originally Posted by Merc 2.5

I'm all about tryin get a 150$ motor runnin for 150 or less lol. That 2.0 piston has identical skirts so had to find marking. But bad thing was I didnt think about it til I was cleanin everything so I had to clean slugs. I'll mark a 2.0 next time tho , ha

So I got the used piston and new rings in, was able to get good compression from the engine, little under 120#s in a few but we should be good to go. Just need some other parts and I will be ready to fire it up. Not bad to have a 200 2.5 for like $300...Finally killed the spider that was laying webs all over the thing....

**Merc 2.5** · 08-07-2020, 06:50 PM

Originally Posted by Aaronhl

So I got the used piston and new rings in, was able to get good compression from the engine, little under 120#s in a few but we should be good to go. Just need some other parts and I will be ready to fire it up. Not bad to have a 200 2.5 for like $300...Finally killed the spider that was laying webs all over the thing....

And its liable to last yrs to come , I got a deal similar to that once and after few odd and ends it had to have , motor ran great for yrs , I sold it. Didn't blow

**phillnjack** · 08-08-2020, 12:33 PM

just lat down some wet n dry paper on a dead flat surface and do a figure of 8 for 5 mins then it will ok ok..... do not sand blast it. . justa bit of wet n dry . I went from this to this with sandpaper so dont let people tell it dont work. mine was extreme and I took of 80 thou, long story.... and yes it now dead flat surface.... I have since put back in the chamfer on the edge and no signs of any damage at all... elbow grease is all you need if you dont happen to have a machinist with a big mill close to you

**Merc 2.5** · 08-08-2020, 03:28 PM

Originally Posted by phillnjack

just lat down some wet n dry paper on a dead flat surface and do a figure of 8 for 5 mins then it will ok ok..... do not sand blast it. . justa bit of wet n dry . I went from this to this with sandpaper so dont let people tell it dont work. mine was extreme and I took of 80 thou, long story.... and yes it now dead flat surface.... I have since put back in the chamfer on the edge and no signs of any damage at all... elbow grease is all you need if you dont happen to have a machinist with a big mill close to you

Now that's a lot sanding. Did u cc the head b4 and after to see where ur at

**FUJIMO** · 08-08-2020, 03:44 PM

Originally Posted by Merc 2.5

Now that's a lot sanding. Did u cc the head b4 and after to see where ur at

...think how much sandpaper that took...

**Chaz** · 08-08-2020, 09:04 PM

Welp , I put me a sparkplug in the center hole , tied a loop on ech end of an ol anchor rope .. laid one over the plug an da other over the ball of me pik-up truk .
I dragged one over the bridge into Stuart. Ate me sum lunch @ Flannigans while the first head cooled off. After lunch, I dragged the other-in back over the bridge , took me an old~man nap while it cooled down .. Perfect 2mm off-a each in ..
Then all Hadd-ta do wuz glue me some gravel on kids spinnin top. Two spins each chamber and the qruinch bands wuz dun .. I did hav-ta use my swiss army knife ta cut the O-rang groovies in .. lookin fer a bedder way ta do that-in rite there.
I don't never use no gradeated pippett ta masure the chambers , i took me a masere cup out the Mrs. kichen , just gather up the sand that gets burn off the spinnin top and musere each chember .. prowd ta say they all .. qurter-cup .. give er take ..

**keefallan** · 08-09-2020, 04:49 AM

Originally Posted by phillnjack

just lat down some wet n dry paper on a dead flat surface and do a figure of 8 for 5 mins then it will ok ok..... do not sand blast it. . justa bit of wet n dry . I went from this to this with sandpaper so dont let people tell it dont work. mine was extreme and I took of 80 thou, long story.... and yes it now dead flat surface.... I have since put back in the chamfer on the edge and no signs of any damage at all... elbow grease is all you need if you dont happen to have a machinist with a big mill close to you

How much did that raise your compression?

**keefallan** · 08-09-2020, 06:05 AM

Originally Posted by Chaz

Welp , I put me a sparkplug in the center hole , tied a loop on ech end of an ol anchor rope .. laid one over the plug an da other over the ball of me pik-up truk .
I dragged one over the bridge into Stuart. Ate me sum lunch @ Flannigans while the first head cooled off. After lunch, I dragged the other-in back over the bridge , took me an old~man nap while it cooled down .. Perfect 2mm off-a each in ..
Then all Hadd-ta do wuz glue me some gravel on kids spinnin top. Two spins each chamber and the qruinch bands wuz dun .. I did hav-ta use my swiss army knife ta cut the O-rang groovies in .. lookin fer a bedder way ta do that-in rite there.
I don't never use no gradeated pippett ta masure the chambers , i took me a masere cup out the Mrs. kichen , just gather up the sand that gets burn off the spinnin top and musere each chember .. prowd ta say they all .. qurter-cup .. give er take ..

DANG!!! DEMS SHOW ARE PURDY!!!!! When ize growz up, dat's how i wants to do me some heads. I'm still waytun to get me pik-up fixed. Gots me a vibrashun in the da tail sekshun. By-da-way, how much was da give 'er take on the cuarter cup? Was dat what yu was shootins fer? And youz got fancy wit dat Swiss ka-niffey of yers. I'd a yoozed a screwdriver and hammer to chizel the groove. LOL!!

No offense to anyone. I am just playing along with Chaz and his funny country bumpkin story.

I'm all about getting something running for nothing. There's just sumthin' about dat!!! But my treachery can only go so far. I've learned that the hard way. And who feels like doing things again when the problem could have been avoided the first time?.....and for not much more usually. Cutting corners will bite ya.......I know.

My only advise to you Aaronhl is this, if yer gonna yuse yuesd perts, measure them out(mic them if necessary), inspect them thoroughly, before using. Mic that piston out for roundness. BTW, I didnt see why you couldnt re-use that head. Soda blast that head. It will remove any dark/black marks still in there. Soda is harmless to aluminum. Then see what it looks like. Then you can lap the head like mentioned above if necessary. Actually, its a not a bad thing to do, just to check head flatness. I bought a 25 dollar glass plate. Its 3/8 thick, 8 inches wide and 3 feet long. It has become a priceless tool for numerous things. If you need to cut alot off, use a heavier grit. But progressively work down to a fine grit.

You can also polish the combustion area too.........if you feel the need. Some do it.......some dont.

**phillnjack** · 10-19-2020, 03:36 PM

well you obviously drove in 3rd gear going by the finished product... did you drive ina big figure of 8 or did you keep stopping and turning them round... checking temps of your tyres incase they were getting too hot while doing this... when you say you used the Swiss army knife , was that a left hand knife or right hand as I am sure it makes a difference when fitting new O-rings knowing what way round you cut the grooves.. Did you find the spark plug gap changed at all whilst towing it round ? ..... I shall definitely give this a try in future, but can you tell us at what mph you found gave the best finish........... save me using sandpaper in the future thats for sure.

**phillnjack** · 10-19-2020, 04:27 PM

yes id id cc the head before and after sanding it down. I wanteda lower cc to begin with and my aim was to get it to around sst60 specs at 28.5 cc at first, but they also have a cut deck .so to me around 26 was hoped for if having it done professionally...... it was 32 cc. to start with ( that was with using some putty on the top chipped bits at the chamfer to make it look right ) my goal was to get down to about 26 to 27 if possible to bring up compression to 160 ish anyway.....
but to get it perfect the cc went down to 24, but I still have to put back a chamfer on top of the chambers so that should raise the cc by about 1 to 1.5 so should be on target for running without the need for race gas.... I think a max of 165 is all I can have for compression without going to race fuel. I can get Tesco momentum 99 that is supposedly 99 octane or shell vmax again supposedly 99. this is ron octane....