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Fri Apr 04, 2014 4:39 pm

To give you some background, I'm building a 1679 out of my stock 1600 DP. I'll already need to get the heads bored out to make room for the larger pistons, but I don't want to come to the machinist with all my parts and have them turn my heads away as not worth the effort.
I also don't have torches or left hand bits to get out stubborn studs. If it's really worth the cost of getting these then I could justify it, but I'm not so sure...
So, how much would it be to take these heads to a machinist and get new studs installed/helicoils in the loose ones/drilled out old studs? And would it be worth it over getting a new set of heads with potentially more life...and power :twisted: ?
Also, I assume those cracks near(on?) the valve guides would be fixed by pressing in new guides?

Thanks for any advice!
Ian

Fri Apr 04, 2014 5:05 pm

hard to see, but it appears you have at least 2 cracked valve guide bosses there....

Fri Apr 04, 2014 5:31 pm

[email protected] wrote: hard to see, but it appears you have at least 2 cracked valve guide bosses there....
He mentioned that

was this an engine that was sitting? looks like aluminum corrosion on the intakes

and no the cracks would not disappear with new guides, my opinion is get new heads, the work needed to rebuild is probably 100 a head, plus another 40 to bore them, so you only need 100 more to get new heads, that aren't iffy

much nicer to get new heads so you can control the head cc as well

Fri Apr 04, 2014 5:33 pm

Crusty crusty get a new set and be better off in every respect.By the time you clean up the heads and repair all the boo boos you will be out of pocket more than if you bought new, and then you still are stuck with an old set

Fri Apr 04, 2014 7:35 pm

long term water damage/corrosion usually
damages the seats/pits them beyond machining.

I have also seen deterioration of the aluminum around the
seats, that erodes the chamber leaving the seats
taller than the surrounding aluminum.

you did not show us pictures of the seats with
valves removed....or the combustion chamber

don't waste your money and time with these heads

Fri Apr 04, 2014 7:52 pm

I agree. They are a bit too far gone. Yes, anything can be repaired, but at what cost?

Fri Apr 04, 2014 9:04 pm

Howard 111 wrote: I agree. They are a bit too far gone. Yes, anything can be repaired, but at what cost?
FUN!!! I always take broken stuff and throw it together just to see if I can get it to run again, just took a 1600, jb welded the sump(hole) threw a bit on the old thrust bearing, dropped in a spare crank sitting around(little out of round but actually not bad otherwise) and two heads pitted beyond the surface of the moon....ran it in our buggy for 2 summers, honestly didn't think it would...oh and one of the lifters had a chunk missing

but in all seriousness if the corrosion hit the chambers, for reliability reasons they shouldn't be used cost wouldn't be there

Fri Apr 04, 2014 9:28 pm

God bless JB Weld! :D

Fri Apr 04, 2014 10:05 pm

75smith wrote:
FUN!!! I always take broken stuff and throw it together just to see if I can get it to run again, just took a 1600, jb welded the sump(hole) threw a bit on the old thrust bearing, dropped in a spare crank sitting around(little out of round but actually not bad otherwise) and two heads pitted beyond the surface of the moon....ran it in our buggy for 2 summers, honestly didn't think it would...oh and one of the lifters had a chunk missing

The above sounds like a GEX rebuild engine :wink:

Sat Apr 05, 2014 9:39 am

That's their performance motor!

Mon Apr 07, 2014 5:45 am

Oh man I didn't click "Watch for Replies" on this topic! Wow, thanks for all the advice everyone.

John@aircooled, yeah at least two, maybe three are cracked.

75smith, the engine was sitting, I couldn't tell you how long, and it was sitting with the intakes exposed and had water sitting in them.
Good to know about the cracked areas not being part of a new guide! That does sound like a ton of work to repair.

Cptn. Calzone, That's kinda what I was thinking, but I wanted to make sure I wasn't just giving up too early on these things!

Rockurob, The heads were sitting exposed to weather without even the intake castings on them so you may be right that the corrosion could be extensive. Even without that, I thought all the other work might put them beyond salvage by myself and beyond cost effectiveness by the machine shop.

75smith, When I have enough dead parts to build a beater engine just for fun when I'm bored (seems like that'll happen sooner than later!) I may well go your way, but I'd like to do it right this time around haha!

Thanks for your advice everyone, I'll start looking for new heads I guess.

:?: Any recommendations for heads on a 1679 engine with a CB 2231 cam (fuel efficent series with a CR of 8.5 max)? I'm looking to keep the stock PICT 34 on it for a while if possible, then maybe switch to duals when I get bored.

Mon Apr 07, 2014 6:40 am

with the small cam any style replacement head should work, the L3's are nice, and if you switch do dual carbs, would be moderately better then actual stock heads...my recommendation is if you can swing the little extra get the L3's

Mon Apr 07, 2014 6:46 pm

Hey Ian; I have a pair of heads from my 75 that you can have cheap. They need a clean up but should be okay. By the way they are stock. I was wondering how the rebuild was going? Message if you need some help.

Mon Apr 07, 2014 8:22 pm

plotch wrote: Hey Ian; I have a pair of heads from my 75 that you can have cheap. They need a clean up but should be okay. By the way they are stock. I was wondering how the rebuild was going? Message if you need some help.
since he's upping the size, he'd do much better getting the earlier heads with the larger valve size

Tue Apr 08, 2014 2:37 pm

True and that's why they are available.

Thu Apr 10, 2014 12:09 pm

Hey Blinky,
I'll buy em new so I have the larger valves installed already, but thanks for the offer! If you're getting itchy to start engine work, you can pm me and we can arrange a return of the stand haha, you know how these things seem to take 30x longer than they should...
Thanks for the advice everyone, those L3 heads look like the ones for me! Now if my RAZZIN FRAZZIN 88mm AA thickwalls would only come in from God-knows-where, I could actually get a start on this project!
Ian

Thu Apr 10, 2014 4:07 pm

sell for scrap.

Sat Apr 12, 2014 2:43 pm

75smith wrote: [email protected] wrote: hard to see, but it appears you have at least 2 cracked valve guide bosses there....
the work needed to rebuild is probably 100 a head, plus another 40 to bore them, so you only need 100 more to get new heads

Where you buying new heads at this price??

Sat Apr 12, 2014 2:48 pm

Jesse1914 wrote: 75smith wrote: [email protected] wrote: hard to see, but it appears you have at least 2 cracked valve guide bosses there....
the work needed to rebuild is probably 100 a head, plus another 40 to bore them, so you only need 100 more to get new heads

Where you buying new heads at this price??

$250 each sounds reasonable for decent heads.. not top of the line, but far from the bargain bin too..

Sat Apr 12, 2014 4:47 pm

I was under the impression they were saying 250 a pair.