Machine shop refuses to install exhaust valve seats

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dibbons

dibbons

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La Paz, B.C.S., Mexico
Had a local machine shop hot tank some small block 915 cylinder heads (1.88/1.60). I asked them if the previous work done on the heads included new exhaust valve seats? The shop "manager" (i guess) looked at both cylinder heads and pointed out a single chamber that had a seat installed and it actually looked a little like it had been pinned (I never installed seats, so I don't know the correct procedure).

Anyway, the manager told me the heads needed a valve job, and I suggested he install new exhaust valve seats in the other seven combustion chambers so they would all be compatible with unleaded gasoline. He swirled his indes finger around one exhaust valve seat and said no, there was was not enough material in the head to do that.

I told him sure there was, how does he think that one exhaust seat had already been installed by a previous owner. No kind of reasoning could change his mind to agree with me, that new exhaust valve seats would be advisable and possible and actually common place for all eight valves.

I had no choice than to pick up my cylinder heads after paying for the cleaning. Before I left, I took the valves out of the carton he had placed them in to find that he only had turned over 15 valves, so he had to run off and find the missing exhaust valve. Then I find one of the valve keepers was missing as well, and he brought me one (don't know if it belongs to my motor or if he scavenged one from somewhere else.

Anyway, now off to find another machine shop (I passed through another shop earlier in the day to see a Sunnen CK-10 in the corner used for finish honing). At the shop where I had the heads cleaned, their honing machine was another brand. When I asked them how they measured cylinder bores for final honing, they said they used a telescoping gauge. When I showed them a foto of a cylinder bore gauge with a dial indicator they said they never had seen such an instrument. I don't think I will return there for a long time.
 
He's an idiot. Find a new machine shop.
 
RustyRatRod said:
He's an idiot. Find a new machine shop.
Click to expand...

I don't know
He sees a job he doesn't think he can do properly and refused to do it

Compare that to the mechanic we read about in the exhaust section of the forum who put the motor mounts on the wrong side and then claimed it improved the cars handling and this guy doesn't seem so bad, at least he is willing to recognize and admit a job he can't perform
 
In the right hands a telescoping gauge is accurate
same as the dial bore gauge. In the wrong hands neither is worth anything. Taking measurements is an aquired feel or skill.
The dial bore gauge is more expensive and purchased for gathering measurements faster.
It is really the machinist's choice as far as which tool he feels he gets the best measurements with.
Good micrometers are very accurate I wouldn't
call him an idiot because he wasn't using an expensive snap gauge for efficiency.
Not saying the guy should be building a performance
engine but there is more than one tool for the job.
One no better than the other. If you are careful about
choosing your machinist he will know what tools he needs to be using.
 
The shop with the Sunnen CK-10 honing machine has there cylinder bore dial indicator hanging right there alongside the machine. I was using a cylinder bore dial indicator back in the 1970's when I was studying Automotive Technology in community college. A shop with only telescoping gauges in 2016 is a little behind the times if you ask me, and one that is afraid to install valve seats even more so.
 
I don't know if he is an idiot or not but if he is busy loosing your parts and can't count to 16 I guess I'd take my stuff and go home too.
 
diymirage said:
I don't know
He sees a job he doesn't think he can do properly and refused to do it

Exactly. He's not a machinist. He should be flippin burgers.

Compare that to the mechanic we read about in the exhaust section of the forum who put the motor mounts on the wrong side and then claimed it improved the cars handling and this guy doesn't seem so bad, at least he is willing to recognize and admit a job he can't perform
Click to expand...

But that still shows he doesn't know how to do a simple machining process that anyone in the automotive machine business should know how to do. You keep takin your stuff there and you deserve whatever outcome you get.
 
I see it as the notion of installing valve seats in 2016
as being behind the times. In the 70/80s we had no choice. Today you can buy heads that have and were designed to have hardened seats. And for about the same cost as the parts and labor to rework the old iron.
Not all iron heads survive the process due to core shift.
I have seen them fall out and hold a valve open even after years of driving. He probably seen it as a waste of your money and his time and he knows it and felt he did you a favor.
When someone comes to me and ask me to do something I know is not ideal or cost effective I politely tell them I can't do it.
As a flip side I find it is also much harder to find a good engine machinist these days in my area.
The older guys and shops that could build any engine no matter what you brought them are all but gone. They have not really been replaced just closed up and gone. I do understand about running into idiot machine shop help nowadays. Even in shops that used to be good. I get your frustration.
 
ssba said:
I see it as the notion of installing valve seats in 2016
as being behind the times. In the 70/80s we had no choice. Today you can buy heads that have and were designed to have hardened seats. And for about the same cost as the parts and labor to rework the old iron.
Not all iron heads survive the process due to core shift.
I have seen them fall out and hold a valve open even after years of driving. He probably seen it as a waste of your money and his time and he knows it and felt he did you a favor.
When someone comes to me and ask me to do something I know is not ideal or cost effective I politely tell them I can't do it.
As a flip side I find it is also much harder to find a good engine machinist these days in my area.
The older guys and shops that could build any engine no matter what you brought them are all but gone. They have not really been replaced just closed up and gone. I do understand about running into idiot machine shop help nowadays. Even in shops that used to be good. I get your frustration.
Click to expand...
You got it, the old time machinist are disappearing slowly the culprit,Crate Engines
 
I don't know how other people run there business but if someone brings in a set of older heads I clean them and check them out, if the seats are so beat out of them that I don't think I can do the job and warranty the work I suggest they look for heads in a little better shape but if I start on there heads and they have a core shift or something that will not work out in there favor I stop and make a phone call. BUT AT THE END OF THE DAY IT'S MY NAME OUT THERE AND I WILL NOT DO WORK THATS NOT FIRST CLASS. When I do work I want the customer to take it to another shop and say take this apart and let me know what you think. I want that other shop to say this is a nice job and done right.
As far as a snap gauge I have them and use them for rough measurements but I have one bore gauge and I'm the only one that uses it I have had helps drop them or set something on them and totaly F them up so now it's me, I don't have to worry I'm the only person boring and honing blocks any way
 
Find another head guy...

If you can't find a good one, let me know, I can give you the number for my head guy... He can install hardened seats and will check the guides to make sure they are good, or he will replace those also... He always cleans up the ports also.... But he's in Detroit...
 
I agree with HEMI446, maybe the guy is an idiot or hack OR maybe he doesnt want his name on them because if they take a dump its his fault, not OP's for trying to revive scrap. If its not for a numbers matching build, why on earth would you not just get a modern set of heads with better quench, larger valves, hardened seats and MUCH better runner volume. I am basing this on machine costs on West Coast in smaller town but guessing close to $300 each by the time the dust settles? Thats using old parts, not new. For a couple of hundred more you can have all new parts and a huge jump in performance. Bare EQ's are $600/pr and assembled with fully polished valves, retainers and locks are $945 shipped to your door. These have 1.92 intake and 1.6 exhaust that ootb flow better than ported 915's. They come with LA intake pattern so you can use your existing manifold.
 
Since the motor has only one new exhaust valve seat installed, and one non-matching connecting rod, it appears there was a problem in the past with one of the cylinders.

We are talking about a Mexican machine shop that charges $25.00 labor to install a cylinder sleeve. Not the same as West Coast prices or anywhere else in the U.S. I need to use the old open chamber heads (915 J) to match the old (NOS) TRW pistons I have. And the local Mexicans don't have the money to replace anything on a motor that they can somehow salvage--they reuse and recycle everything here.

I am not going to throw the heads out yet-the valves are practically new and it appears the valve guides have already been replaced by a previous owner. I suppose I could run the motor for awhile with the stock exhaust valve seats, if the unleaded gasoline causes some unduly wear, i can try the valve seat option at the time of the next rebuild. Who knows if my project car will ever accumulate enough road miles to even worry about the valve seats?
 
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$25/hr is a far cry from machine shop prices in the states. I have some experience with getting stuff done in Mexico/Baja working on pit crews for desert racers back in the 80's. It was always a colorful adventure with some interesting techniques to repairs...sounds like you can get it done super cheap with right guy.
 
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