Cyl Head/Valve Job Repair

[mopowers]

I recently bought a second hand set of Trick Flow 190 heads. One chamber has been repaired because of a dropped valve I believe (or something else). It appears that the shop that repaired it replaced the intake seat.

However, I noticed the new seat has a larger ID which leaves a slight ridge around the base of the seat (Green arrows). It also looks shorter and the factory TF seat leaving ridge on top of the valve. Maybe because it's missing a top cut? Are these a big deal?

Also, The new seat looks to only have a single seat cut, while the other factory Trickflow seats have what appears to be 3-4 angle cut (can't really tell). It looks like Summit sells replacement seats for these heads.

Should I go ahead and pick one up and have a shop install it and cut the seat to match the factory seats in the other chambers? I already plan on taking the heads to the machine shop to have the deck surface checked and skim cut if needed. I originally planned to lap the valves and reassemble myself, but I'm wondering if it's worth having this seat replaced/re-repaired, or springing for a complete valve job on both sets. Thoughts?

Out of curiosity, I ran some lapping compound on the valve/seat and it looks like it'd seal as-is. It just doesn't match the others. The install height for the valve spring is dead nuts on the 1.950" it should be though.

Other chamber with factory TF valve job:

 

[Oldmanmopar]

I would not be happy seeing those pictures.

 

[RAMM]

Run it. Unless you want to spend a whole lot more $$$$. Or call Summit- they own TF. Ask them if they repair their own castings, if they do, send it back. J.Rob

 

[Newbomb Turk]

I’m with RAMM.

Unless you want to do all that work over and pay for it, just run it.

It’s sad people do work like that.

I usually defend machine shops but that is inexcusable and indefensible.

When I do that type of repair I use a seat that has a smaller ID than what that is.

That way you are sure to get all the valve job on it.

Since it looks like the chamber needed welding I would have welded up the OD of the seat pocket in the head.

Then I leave a small area next to the exhaust seat (which BTW if it hasn’t been replaced means I would NOT run it) so I have a witness mark to set seat depth.

Yeah, they didn’t pull the exhaust seat. We have no idea how much heat they put into the head doing the welding but that seat could fall out.

It’s bad technique to leave a seat in like that. Just stupid.

Anyway, looking at it closer I have a hard time saying run it.

When you weld on a head like that, in the chamber both seats and the guides need to be pulled. You increase the chance of the seat falling out leaving it when welding that close to it.

By close to it I mean anywhere in the chamber.

In defense of the shop, maybe they felt that the welding in that chamber was far enough away from that seat it’s ok.

We don’t know what they were thinking but I don’t know a machinist whose would leave that exhaust seat in like that.

What a shame.

 

[Newbomb Turk]

Run it. Unless you want to spend a whole lot more $$$$. Or call Summit- they own TF. Ask them if they repair their own castings, if they do, send it back. J.Rob

If that’s how TF does the repairs I wouldn’t give them a second shot.

 

[PRH]

It looks to me like there is a seat sitting on top of what’s left of the original seat, or they just remachined the original seat in a way the leaves you with what you have there.


If you look at the darker gray material that’s just above the obviously aluminum of the head casting, you can see it still has the cnc machining marks in it from when it was ported.

But to address the two things specifically called out by the OP with the arrows…….not pretty, but not a big deal either.
Part of why you (hopefully) got a deal on them.

 

[PRH]

If you look at where the two seats meet, you can see it appears the exhaust seat is installed after the intake seat.

If the intake seat had been replaced, the OD would be “full round”, but instead it still has the notch in it where it’s interlocked with the obviously not replaced ex seat.

At least that’s how it appears from what I can tell by looking at a pic on my phone.

 

[MOPAROFFICIAL]

Is the stem height matching the rest?
If it is.. then you would be looking at fixing the vj on that one but having to cut the stem down to match the height of the rest. Starting over on the vj could be costly.

 

[Newbomb Turk]

If you look at where the two seats meet, you can see it appears the exhaust seat is installed after the intake seat.

If the intake seat had been replaced, the OD would be “full round”, but instead it still has the notch in it where it’s interlocked with the obviously not replaced ex seat.

At least that’s how it appears from what I can tell by looking at a pic on my phone.

View attachment 1716376010

I thought they replaced the exhaust seat too but looking at I can’t believe they did a nice radius on the exhaust and that crap valve job on the intake seat.

 

[mopowers]

I appreciate all the feedback guys.

Run it. Unless you want to spend a whole lot more $$$$. Or call Summit- they own TF. Ask them if they repair their own castings, if they do, send it back. J.Rob

That's in interesting thought. Thank you. I may call Summit to see if they have a shop that does TF repairs.

I’m with RAMM.

Unless you want to do all that work over and pay for it, just run it.

It’s sad people do work like that.

I usually defend machine shops but that is inexcusable and indefensible.

When I do that type of repair I use a seat that has a smaller ID than what that is.

That way you are sure to get all the valve job on it.

Since it looks like the chamber needed welding I would have welded up the OD of the seat pocket in the head.

Then I leave a small area next to the exhaust seat (which BTW if it hasn’t been replaced means I would NOT run it) so I have a witness mark to set seat depth.

Yeah, they didn’t pull the exhaust seat. We have no idea how much heat they put into the head doing the welding but that seat could fall out.

It’s bad technique to leave a seat in like that. Just stupid.

Anyway, looking at it closer I have a hard time saying run it.

When you weld on a head like that, in the chamber both seats and the guides need to be pulled. You increase the chance of the seat falling out leaving it when welding that close to it.

By close to it I mean anywhere in the chamber.

In defense of the shop, maybe they felt that the welding in that chamber was far enough away from that seat it’s ok.

We don’t know what they were thinking but I don’t know a machinist whose would leave that exhaust seat in like that.

What a shame.

Thank you. That's an interesting thought about the exhaust seat and guides. I hadn't even thought of replacing those since they look to be in good shape. After looking closer at the exhaust seat, it appears that there is a very slight ridge at the base of the seat (red arrow), whereas none of the others seems to have this ridge. Could this be from movement from the heat of welding? The valve lapped in fine, if that even matters.

If that’s how TF does the repairs I wouldn’t give them a second shot.

I don't believe TF did this repair. I'm 99% sure it was a local machine shop.

It looks to me like there is a seat sitting on top of what’s left of the original seat, or they just remachined the original it in a way the leaves you with what you have.

If you look at the darker gray material that’s just above the obviously aluminum of the head casting, you can see it still has the cnc machining marks in it from when it was ported.

View attachment 1716376009

You are correct! I didn't mention that part because my post was already getting really long. It's pretty apparent that when the shop installed the seat, they left part of the original seat. That's the only way I can see why there'd be that ridge around the base of the new seat.

When I take the heads in to check the deck surface for flatness, I may just see what they'd charge to replace that seat and make it just like the others. I see Summit sells the TF seats, so I could even take that in if we decide to go that route. Trick Flow Specialties TFS-61400271-1

If you look at where the two seats meet, you can see it appears the exhaust seat is installed after the intake seat.

If the intake seat had been replaced, the OD would be “full round”, but instead it still has the notch in it where it’s interlocked with the obviously not replaced ex seat.

At least that’s how it appears from what I can tell by looking at a pic on my phone.

View attachment 1716376010

That's an interesting observation too. Here's a straight on shot (below). You're right though, it does kinda look like the exhaust seat was installed after the intake. The exhaust looks exactly like all of the others though, so I would say it wasn't replaced. Strange!

 

[PRH]

From what I’m seeing, it looks to me like the original intake seat was never actually removed.

What’s there now might be a seat…….”inside” what’s left of the original seat.

 

[mopowers]

From what I’m seeing, it looks to me like the original intake seat was never actually removed.

What’s there now might be a seat…….”inside” what’s left of the original seat.

That makes sense. Would you replace the seat, both seats, or run it?

 

[mopowers]

Is the stem height matching the rest?
If it is.. then you would be looking at fixing the vj on that one but having to cut the stem down to match the height of the rest. Starting over on the vj could be costly.

I'll have to check stem heights. My dumbass forgot to check before disassembling the heads.

 

[gzig5]

That makes sense. Would you replace the seat, both seats, or run it?

Looks to me like they bored out the original intake seat until just before the exhaust seat overlaps it so they didn't have to mess with the exhaust for some reason. So the new seat is sitting in a thin shell of the old seat. Either way it looks sketchy. I don't think I would feel good running it that way and would cut out the entire intake seat and replace it. The exhaust seat is a crapshoot if the chamber was welded on. I don't know what to say about that one. Really depends on how much heat they put into the chamber while welding. If they protected the exhaust with a heat sink, it should be OK. On the other hand, it probably doesn't cost much more to replace the exhaust while they do the intake seat. Then you have peace of mind.

 

[PRH]

That makes sense. Would you replace the seat, both seats, or run it?

If it’s a seat in a seat, I’ve never done it that way(or seen it before), but I’d replace that.

Imo, exactly what was done for the repair needs to be determined before deciding on the path forward.

If you determine it’s just the original seat, remachined, I’d probably just leave it.

I’d scotch-brite around the top of the seat and look at it closely with a magnifying glass to help assess what’s going on.

I’d also try and get some contact info for who did the repair and maybe make a call, and they could just tell you what was done.

 

[LO23M8B]

Buy one new head.

 

[mopowers]

If it’s a seat in a seat, I’ve never done it that way(or seen it before), but I’d replace that.

Imo, exactly what was done for the repair needs to be determined before deciding on the path forward.

If you determine it’s just the original seat, remachined, I’d probably just leave it.

I’d scotch-brite around the top of the seat and look at it closely with a magnifying glass to help assess what’s going on.

I’d also try and get some contact info for who did the repair and maybe make call, and they could just tell you what was done.

After looking at it closer, I'm starting to think it may just be a recut on the original seat. If that's the case, they also cut the ID and top surface. Do they even make cutters like that? (probably a stupid question). I'm just wondering why they wouldn't have just recut the seat angle and called it good.

When I take it to the machinist, I'll have him weigh in. If he thinks it's a "seat within a seat", I'll have him replace it with a solid single seat and look at the exhaust side too.

The heads were acquired very inexpensively, so I'll make the work one way or the other. I've already repaired most of threads, so I'm pretty determined to make it work.

 

[PRH]

I suspect there was some ugliness on the seat insert below the 45, and it was just bored a bit to get rid of it.
Then a slight plunge cut on top with a zero degree cutter to square up the top, and a recut of the seating/top/bottom angles…….and it would look like what you have.

 

[MOPAROFFICIAL]

After looking at it closer, I'm starting to think it may just be a recut on the original seat. If that's the case, they also cut the ID and top surface. Do they even make cutters like that? (probably a stupid question). I'm just wondering why they wouldn't have just recut the seat angle and called it good.

When I take it to the machinist, I'll have him weigh in. If he thinks it's a "seat within a seat", I'll have him replace it with a solid single seat and look at the exhaust side too.

The heads were acquired very inexpensively, so I'll make the work one way or the other. I've already repaired most of threads, so I'm pretty determined to make it work.

What they did was they cut the seat that was in the head down and then put a slightly larger OD seat on top of that. They did not want to get into water. They needed to get a .010 larger seat so that it would have interference fit ...because you can't just pop a seat out of aluminum head and put the same size back in. I'm sure it was to not get into water first and foremost, but this also kind of keeps the throat closer to cnc size...though raised up a little.

 

[mopowers]

I suspect there was some ugliness on the seat insert below the 45, and it was just bored a bit to get rid of it.
Then a slight plunge cut on top with a zero degree cutter to square up the top, and a recut of the seating/top/bottom angles…….and it would look like what you have.

Thanks again for the input. I'm anxious to hear what my machinist has to say. My eyes just aren't trained enough to figure out what was done.

 

[mopowers]

What they did was they cut the seat that was in the head down and then put a slightly larger OD seat on top of that. They did not want to get into water. They needed to get a .010 larger seat so that it would have interference fit ...because you can't just pop a seat out of aluminum head and put the same size back in. I'm sure it was to not get into water first and foremost, but this also kind of keeps the throat closer to cnc size...though raised up a little.

You may be on to something. I just measured, and the OD of the odd seat and it measures 2.130". The OD of the other intake seats looks to be 2.110". They may have replaced the seat with on of a slightly larger OD like you suggested. But I'm having trouble understanding why the exhaust seat is still round at the OD as PRH pointed out. Almost like the exhaust seat was installed after the intake seat.

Either way, if that is the case, would it be worth having a shop touch up seat cut add a 30 and 60 if there's room? Would be worth blending the ridge from the original seat? Or just run as-is. Assuming this is what was done.

 

[PRH]

I looked up the replacement intake seat on the TF site to see if they listed the OD.
They don’t, but I found the pic(which may or may not be a pic of a seat for those heads) pretty interesting.

would it be worth having a shop touch up seat cut add a 30 and 60

What I’m seeing looks like there is a top and bottom angle added to the new 45.
Whether that’s a 30 and a 60……can’t tell by a pic.

 

[Newbomb Turk]

If I was looking at that head from the perspective of using it I’d fix it.

The seat in a seat deal is new to me. That’s a 2.02 valve. I have no idea what OD seat TF uses but is use a 2.125 OD seat with an ID smaller than the throat.

I’d pull both seats and knock out the guides in that cylinder.

I’d weld up that ugliness in the chamber where it was either previously welded or whatever someone just ground the hell out of it.

I’d weld up both seats.

Then I’d finish it just like you would if you just needed to replace the seats.

The are issues for the OP though.

First he has to find someone capable of doing the work competently.

Then he has to pay for it.

Certainly the former will evidently be difficult to do. A seat in a seat is idiotic to me.

I suppose there may be a time for it but to me, it’s a repair done by someone without the tools or skills (or both) to fix it.

I only suggest the repair above because I can weld and machine it.

If I had a seat and guide machine I’d have you send me the head and I’d repair the head first cost plus 15% for a FABO member.

I’ve found a Bridgeport that I can get for a smoking deal. I just need to figure out some details.

Then I’d need to buy the tooling. That’s the wallet exploding part.

 

[Earlie A]

Another option would be to sell the damaged head as it is. I've been looking for a damaged or used TF head to do some (practice) porting with. PM me if interested. Maybe we can work out something that works for both of us.

 

[1MeanA]

Buy one new head.

That is the best route. It needs to be welded up. Can you apply that much heat to the head without a total rebuild?