Early Panhead valve seats

[SRG]

I have a 1952 Panhead Hydraglide I restored and I have 11,600 miles on it. I have had the rear cylinder exhaust valve seat drop out twice. It has resulted in complete destruction of the piston and steel particles throughout the whole oiling system and engine. I built the complete bike except....the engine. I don't have the tools to do an engine, but I would like to learn. The real problem is, did HD have a problem with the valve seats on the early Panheads? What do any of you know about this? It is 100% stock. I love this bike but I'm not in the money or patience to have crap like this happening every 5000 miles. Thank you for any feedback.

[Ohio HD]

In 1952 I think they were casting the bronze seats into the head. I'm not sure they can fall out.
It's been better than 25 years since I'm had my hands on a set of Pan heads, but that's how I remember them.


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[Don D]

A qualified shop can fix this by renewing the counterbore and fitting a seat with the proper press fit then a valve job to restore the protrusion. Guides would likely need attention at the same time. Many times when I work on these I replace everything with modern parts for a good result. It gets expensive.

[SRG]

Thanks for the replies. I had the current seat that dropped out returned from the head guy with a statement, "No guarantees on this seating", no explanation. My guess is the seat pushed in too easily, but that's a guess. I found a back up head at Davenport and had the same guy do it for me for a backup. Two things stood out. First, there are damned few rear OEM heads for 52 panheads to be found. That's a heads up to me. Second, is the same thing going to happen with this head? I'm to the point where I want it done right. In my opinion this motor should last 60 to 80 thousand miles without a problem if properly taken care of, and not trying to keep up with the new bikes. It's very original, but I would be willing to make changes to make it more dependable as long as I still retained the OEM parts removed. I have been told the original panheads had this problem, but by the time the factory discontinued the panhead in 1965 the problem had been solved. 

[Ohio HD]

Truthfully, if I were to have a set of Pan Heads worked on, I'd send them to someone who's done many of them, and does it for a living. The two names that come to mind are Scott Palmer and Jim Libonati. Both have been doing work on early HD's for over 25 + years. This wouldn't be their first one. It's the route I would go.

Scott Palmer - http://hillsidecycle.com/

and

Jim Libonati - http://www.mega-flo.com/index.htm

[moose]

not sure if they are still in business but   Flo headworks used did a set for me many many years ago

[Ohio HD]

There also used to be a guy around Cleveland that had a spray weld process that built the bronze seats back up, keeping the original seats all bronze. But I think he may have closed up the doors a few years ago.

[Ohio HD]

Well, I just found out the fella passed away, his name was Don Sullivan, his company was Head Hog.


RIP   

[Snowyone]

Baisley Hi-Performance did the heads on my 53.  They've only been run on the test stand thus far but Dan said that's what his Dad cut his teeth on in the beginning so I can only hope.  They've been my go to head porter for both Evos, and Twin Cam both with good results.

[prodrag1320]

ive done many early pan seats over the years,not a big deal.the interfit has to be closer than later heads as they have a tendency to crack in to much of a press fit is used.

[Don D]

My goodness there are many shops that can replace these seats.  Even keyed seats described. Have done many Triumphs which have to be cut out and seat bores welded up before a conventional seat can be used.

[jimlibo]

That's a nice pic of a good looking reseat job on a set of STD Panheads.It's an entirely different ballgame when working with original HD vintage units though. Take in more of THAT type of work and you will find out the hard way like most of the more experienced have. BTW what the hell is a "keyed valve seat" ?

[Don D]

What Ohio hd was eluding to I thought, never seen a harley with them, they are spined and cast in during the aluminum mold process. Triumphs use them. My experience with the antiques thus far has been welding most of the time.

[Deye76]

not sure if they are still in business but   Flo headworks used did a set for me many many years ago

Perry Kime @ Flo Headworks has saved many pan heads.

[Brrrap]

Scott Palmer at Hillside did my 1959 Pan's heads nearly 9 years ago. Seats, valves and guides. Even had the exhaust bungs cut out and new ones welded in. I cant say enough good about that shop.

[Cracked Head]

That's a nice pic of a good looking reseat job on a set of STD Panheads.It's an entirely different ballgame when working with original HD vintage units though. Take in more of THAT type of work and you will find out the hard way like most of the more experienced have. BTW what the hell is a "keyed valve seat" ?

That's for damn sure too tight-a crack,too loose falls out.the aluminum turns into rubber when hot.Too old ,after countless heat cycles.Easier with oversize valves in the old bronze seats.

[pan620]

I think the problem is you can never get all the brass cut out as they were a keyed type seat, so when you put hard seats in you have 3 different materials expanding at different rates, and as some people have said if you put them in tight the head will crack, so i agree with Cracked Head over size valves will work most times.

[wreck74]

These old panhead heads are so pouris it's more than likely going to drop a seat no matter how good of a job is done. If you want reliablity, go with a set of STD cylinder heads.

[Hybredhog]

These old panhead heads are so pouris it's more than likely going to drop a seat no matter how good of a job is done. If you want reliablity, go with a set of STD cylinder heads.

  When the $$ is all said & done, this is probably the easiest way out. Not saying there aren't good people that can do good work, but Aluminum get old & weak, and a set of STD's would let you sleep at night. I'm dealing with set of S&S hybred Pans right now on a '67, nice set up with hydraulic lifters, shovel ex & intake, but are cramped for frame clearance.

[Bangkok BOB]

That's what a good set of seats looks like

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[Hillside Motorcycle]

We also built a dedicated fixture years ago to re-surface the cylinder head gasket surface in any of our vertical mills, to insure all is well.

[MikeL]

That's what a good set of seats looks like

  [attach=0,msg1348612]

can you still get leaded petrol in your country?

                                                                                                                                                                   MIKE

[Bangkok BOB]

No.

Seats in bronze are hard and ok for lead free fuel.
Its valves that must be changed.
I put in kibblewhite valves and hardware.
Regards. B.B.

[JSD]

These old panhead heads are so pouris it's more than likely going to drop a seat no matter how good of a job is done. If you want reliablity, go with a set of STD cylinder heads.

STD are Closed Down worst luck

[CraigArizona85248]

Yeah, I had to go with VTwin repop heads since no STDs were available anymore.  The castings are actually pretty decent.  I upgraded the upgraded valve springs and had a 3-angle valve grind done on them before installing them (see my thread from a couple months ago for the details on the small issues I ran into).  Overall, I'm pretty happy with them.  Just don't expect to install them out-of-the-box and run them.

-Craig