Freshly machined head-won't fit easily

[AwD4g63TsI]

I am in the process of putting a freshly machined head back on to my block. I've got ARP head studs and the head doesn't slide smoothly over the studs. It's a VERY tight fit. 2-3 of the studs are making contact with the head all the way down. The head makes it all the way down but I am very uncomfortable with the contact and how it might affect the HG clamp force. This is my 3rd build and my previous two slipped on beautifully with no hassle. Anybody have any ideas or run in to this before? It's a 6 bolt head and block

 

[lil corb]

Is it a 6 bolt or a 7 bolt head? 7 bolts use a smaller size headstude 11mm I believe where as the 6 bolts are 12mm.

 

[AwD4g63TsI]

It's a 6 bolt head and 6 bolt block

 

[TSIfreek]

It's a 6 bolt head and 6 bolt block

make sure the cams spin freely with the lifters out and if that is ok its going to have to go back to the shop to have the head stud holes punched out as the casting has shifted a little . No big deal just make sure the cams spin freely!!
You can have them punch them out to 1/2" and call it a day.
I had the same problem on my head.

 

[pos4g63]

Did the head fit before you got it repaired?

 

[AwD4g63TsI]

make sure the cams spin freely with the lifters out and if that is ok its going to have to go back to the shop to have the head stud holes punched out as the casting has shifted a little . No big deal just make sure the cams spin freely!!
You can have them punch them out to 1/2" and call it a day.
I had the same problem on my head.

Thanks-I had never heard of opening up the holes before but that makes me feel a little better because I had thought of trying to do something like that. Cams spin just fine.

pos4g63-the head fit fine when it came off and the factory bolts made no contact when I took them out.

 

[ed1380]

The studs are installed after the head is installed. They're not all 100% parallel and it's binding the head up.

Install head. Place washers in respective places. Then install studs.

 

[AwD4g63TsI]

The studs are installed after the head is installed. They're not all 100% parallel and it's binding the head up.

Install head. Place washers in respective places. Then install studs.

I actually tried this after getting so much resistance. However, the problem is that the holes are mismatched far enough that the offending studs won't start threading after the head has been put on-the alignment is just far enough off that it can't be done.

 

[TSIfreek]

Thanks-I had never heard of opening up the holes before but that makes me feel a little better because I had thought of trying to do something like that. Cams spin just fine.

pos4g63-the head fit fine when it came off and the factory bolts made no contact when I took them out.

Cool good to hear the cams spin with no binding. Yes its best to have the holes in line straight with the head surface for best camping force evenly threw out the head.

 

[romeen]

I actually tried this after getting so much resistance. However, the problem is that the holes are mismatched far enough that the offending studs won't start threading after the head has been put on-the alignment is just far enough off that it can't be done.

Something is wrong if the holes between the head and block won't line up. I don't know if drilling the bolt holes larger would be a good idea. I would be worried that it won't fix the underlying cause and could cause problems with the head gasket. But, admittedly, I've never ran into this problem.

Are the alignment dowels in place?

 

[JacksonAuto]

This is pretty common. It's usually because as you're sliding the head over the studs it's not perfectly lined up.The solution is to set the head on the block and then install the studs. This also reduces the risk of scratching the deck surface.

 

[bryanwheat]

You do still have dowels in the block right?

 

[BogusSVO]

How much was the head milled?

To me it sounds like the head was warped very bad, causing the head bolt holes to twist in the head casting. If this was the case the shop should have stopped and called you and informed you of how bad it was warped, A choice should have been made at this point to A) replace the casting or B) have the head strightened.

If this was the cause, and the cams can be spun by hand with no binding, and the head has been milled properly. you should be fine.

Now reaming the head bolt holes will have to be done on a machine with a reamer.

Remers do not flex near as much as a drill bit.

A drill bit will follow the hole and may or may not correct your issue.

A reamer will "force" the hole to become straighter.

http://www.dsmtuners.com/forums/cylinder-head-short-block/341885-oil-port-mod-2-4g63t.html

 

[AwD4g63TsI]

The dowels are in the block. I just got back from being overseas for 3 years and this work was done before I left, so I honestly can not remember how much was shaved off the head. I also had valve seats cut for 1mm oversize and bronze guides put in. I will try one more time without studs in and then try to massage it as much as I can once it's over the dowels to get the holes lined up.

Thanks for all the input

 

[BogusSVO]

Measure the head thickness and it can be figured out how much has been milled from the head.

http://www.dsmtuners.com/forums/cyl...how-measure-4g63-cylinder-head-thickness.html

 

[AwD4g63TsI]

Measure the head thickness and it can be figured out how much has been milled from the head.

http://www.dsmtuners.com/forums/cyl...how-measure-4g63-cylinder-head-thickness.html

Thanks for the link to the write up-very handy stuff.