New heads or heli coil?

[Vamstad]

1979 2.0 FI Federal

I have searched the forums and it seems like a lot of factors depend on which (new or heli-coil) to choose.

So, here is my story....

About 5K ago I changed the plugs in my engine. One of them, #2, came out with a couple of threads. I chased it and everything was fine...until the other day when my motor spit it out. I carefully replaced it and it lasted another 10 miles before spitting it out again. I looked carefully and found that the hole was stripped.

This motor was rebuilt about 17k ago with new (or rebuilt) heads. I kind of feel that when I remove the engine to get at the head, I should just buy and install all new heads. But, another part of me says to heli-coil (or similar) it and avoid a $500-800 cost of new heads because, the heads are kind of new (this assuming that I don't find any other head issues when I get to them).

Any thoughts or advice? What things should I look for in the condition of the heads?

Thanks!
_________________
Fear is the mind killer.
1979 Federal Westfalia
2.0 FI

[Bleyseng]

The engine was rebuilt 17k ago so the heads were rebuilt or new?

If the heads were rebuilt they are probably going alittle soft to pull the threads. I would helicoil em but start plan B and save up for some of these. NEW Super Stock Complete-7417 #16894- http://www.aircooledtechnology.com/store/product.php?productid=16894&cat=283&page=1
which are Brand new castings with upgraded hardware, seats, guides,valves. These are made to last.

Old rebuilt heads have seen tons of heat cycles and slowly the aluminum changes becoming soft. Seats pound into the heads, studs pull, and threads crap out. The aluminum only lasts so long.....
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70 Ghia Black convert-9/69 build date-stock w/133k 1600 SP-barn find now with a rebuilt tranny and engine
77 Westy 2.0L w/Ljet, Camper Special engine-95hp and with LSD!(sold)
76 Porsche 914 2.1L L20c, 120hp Djet (sold)
87 Syncro Westy Titan Red 2.1L 2 knob 100k miles

[SGKent]

helicoil or threadcert is fine howver Bleyseng is correct, may have been overheated and aluminum getting soft. That spells trouble if a seat pops out. You might also ask Ron at Bus Depot who does his heads as they have some reasonable budget ones.
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“Most people don’t know what they’re doing, and a lot of them are really good at it.” - George Carlin

[Vamstad]

The PO mentioned that he had destroyed a head (I think he said melted) and that it meant a motor rebuild. I forgot if he mentioned if the heads were rebuilt or new. I'll probably be able to tell when I get them off...
_________________
Fear is the mind killer.
1979 Federal Westfalia
2.0 FI

[Vamstad]

I hear that heli coils are strong and should be used if the head is in good shape. Does anyone have any bad experiences with heli coils?

A buddy of mine actually mentioned that I should just heli coil all four of the plug holes as the heli coils are strong! Anyone else recommend this on rebuilt heads?

BTW...the massive type IV heads at 2K sound like they are impressive...Someday when I live outside of CA, i'll look into the camper special! Cool stuff, man.
_________________
Fear is the mind killer.
1979 Federal Westfalia
2.0 FI

[keifernet]

I am not a fan of helicoils for spark plug repair. For some other threaded application that is to be bolted/tightened up and won't be back apart but occasionally if ever or need be sure.

If something has to be used I prefer an insert for the spark plugs. As you want the insert to hold up to remvoal of the plugs... helicoils often mess up on people from taking the plugs in and out during routine maintenance.

I am sure there are others who disagree but this is just "IMHO and EXPERIENCE" posting as I have seen them fail many times more than an insert.

You should have no problem findind a "kit" with the 3/4" longer inserts you need for a bus head.

[GusC2it]

[oorwullie]

german engineering.

[Vamstad]

Called a local shop and they said that they never heli coil a spark plug...that they use inserts on plugs in air-cooled VW motors and it would cost about $50. Looks like the route I am going to go.
_________________
Fear is the mind killer.
1979 Federal Westfalia
2.0 FI

[GusC2it]

[bigbore]

I use them all the time. thay are great without them I could save so many things. if you use the in-surt's for spark plugs use the one withont the shoulder on the top thay like to come out with the spark plug no matter loctite you use. the ones that you use a driver and set them work great thay don't back out at all. I get them from Napa.

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where its cold and snowy

[Russ Wolfe]

The ones shown above are not the wire heli-coils, like most people think of for heli-coils.
I use the ones shown, as they are staked in after installed.
Timesert makes one also.
The wire heli-coils will work if you are doing it with the head on the engine.
Hard part, is breaking the little install tang off, without it dropping into the cylinder.
My installation tool, had a stop collar on it to install them to the exact right depth.
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Society is like stew. If you don't keep it stirred up, you end up with a lot of scum on the top!--Edward Abbey

Gary: OK. Ima poop.

[earthnsurf]

Make sure the heli coil goes in perfectly straight! Ask me how I know.

[bigbore]

[Vamstad]

****Update****

My head just spit out the insert and plug going up a steep hill in third. The insert seemed to have lasted about 5 years...

I had already planned for this day by getting new AMC heads (square port for my '79). Now I will send them away to get improved with new seats, springs, valves and such...

My new question is: Now that I am going to pull the heads on this motor (recently rebuilt, 25K ago) what else should I do? Leaving the bottom end alone seems reasonable from the forums that I have read. New rings? What should I look out for/dig into?

Thanks in advance!
_________________
Fear is the mind killer.
1979 Federal Westfalia
2.0 FI

[SGKent]

[Vamstad]

Great! Thanks for the info!

When I get it apart, I'll take some photos of the Pistons to post...
_________________
Fear is the mind killer.
1979 Federal Westfalia
2.0 FI

[a-marshal]

[Vamstad]

Just got my heads back from Headflow masters...damn, they look sexy!

I will post photos in the next day or two.

I have a question about the studs. With the brand new heads, there is a package of studs for the manifolds and the like. How should I install these? with two nuts? Any lock-tight or anything? Any kind of torque setting?
_________________
Fear is the mind killer.
1979 Federal Westfalia
2.0 FI

[SGKent]