What the hell am I doing?, head rebuild estimate |
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What the hell am I doing?, head rebuild estimate |
bd1308 |
Oct 17 2006, 02:25 PM
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#1
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Sir Post-a-lot Group: Members Posts: 8,020 Joined: 24-January 05 From: Louisville,KY Member No.: 3,501 |
Damn this stuff is like greek.I have either a set of 2.0 bus heads I could rebuild, or 1.7L 914 heads and I'm just wanting something I could cruise with for 100k miles.
I understand these new valve seat installation methods are much better than stock, and i printed out len's pricelist and i'd need somethign like this. 1.7L 914 heads: *Install Valve Seats ($30.00*8)=$240 *Install Valve Guides ($100*2)=$200 There arent any cracks on these heads that I am aware of (currently running them now, no problems) Should I send them bare or with valves so the valves can be matched with the head? I dont care about performance, I drive 65-75 and dont care how long it takes to get there, just as long as its reliable to 100k miles at least. I wish I lived next door to someone who could be like look man, you need this done, and it'll be this much, and if you do it yourself with my machines you'll get it done cheaper or something to that effect. b |
bd1308 |
Oct 17 2006, 02:26 PM
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#2
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Sir Post-a-lot Group: Members Posts: 8,020 Joined: 24-January 05 From: Louisville,KY Member No.: 3,501 |
Well I have a set of good looking 1.7L heads I could use in my 914....
Like I said, I need someone to look at what I have and suggest something. The bus heads may work, I may just slap em on my new bus to get it rolling while I build my 1.7L engine for my 914. |
Chris Pincetich |
Oct 17 2006, 02:35 PM
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#3
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B-) Group: Members Posts: 2,082 Joined: 3-October 05 From: Point Reyes Station, CA Member No.: 4,907 Region Association: Northern California |
I seem to remember Jake and Len talking about 1.7 heads on the "Budget Rebuild" IV Dimension radio show several weeks back, cause I have a 1.7 too, and they said that 1.7 heads are great and last forever and rarely crack or drop a valve seat or even need new seats a all. Chances are the 1.7 heads are good to go. Maybe you could post some high res pics here for critique.
(IMG:style_emoticons/default/beerchug.gif) |
bd1308 |
Oct 17 2006, 02:40 PM
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#4
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Sir Post-a-lot Group: Members Posts: 8,020 Joined: 24-January 05 From: Louisville,KY Member No.: 3,501 |
Hmm, well thats the thing. I loev the 1.7L engine, and so far ive been getting old 1.7L engines for little to no money to put in. I really appreciate the support I have gotten, but am starting to feel that I need to do my own work, and start paying up on this car.
I have a set at home, i'll post pics if I remember when I get home. I thought about running this engine until its abotu to lay over and then use my 1.8 block to build up a super nice 1.7L engine to put in, with the RAT 9550 cam and polished crank, with rod bearings installed, etc. I think I have domed pistons too, which are supposedly are getting harder to find. |
Bartlett 914 |
Oct 17 2006, 02:47 PM
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#5
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Advanced Member Group: Members Posts: 2,216 Joined: 30-August 05 From: South Elgin IL Member No.: 4,707 Region Association: Upper MidWest |
I think maybe you are too worried about dropping valve seats. I know this has happened before to you. This usually only happenes when the heads get too hot. Your first motor had that single carb and ran hot. I don't remember why the other blew. I think you just had a run of bad luck. There are an awful lot of motors out there that this hasn't and will never happen to them. Do a normal rebuild and only change the seats if necessary (cracked, badly worn or loose).
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bd1308 |
Oct 17 2006, 02:50 PM
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#6
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Sir Post-a-lot Group: Members Posts: 8,020 Joined: 24-January 05 From: Louisville,KY Member No.: 3,501 |
Maybe I am a little paranoid about dropping seats, but in three engines that I have had, only one had problems, and that was from my stupidity plus the ignition timing being WAY advanced and from the single carb and trying to run it when gas flow was obstructed.
OK. So replace seats ONLY if they sit lower than the rest? I seem to recall that most of the time the seats usually just fall into the bore of the valve, not causing ultimate destruction. I feel better (IMG:style_emoticons/default/smile.gif) I guess it all comes down to this: stock or not, if the temp doesnt go well over 400F, there shouldnt be any problems. I mean if a hippie can drive a bus for many miles without major trouble, I should be able to with all of the dwell meters and timing lights and CHT guages I have, right? |
Bartlett 914 |
Oct 17 2006, 03:12 PM
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#7
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Advanced Member Group: Members Posts: 2,216 Joined: 30-August 05 From: South Elgin IL Member No.: 4,707 Region Association: Upper MidWest |
Maybe I am a little paranoid about dropping seats, but in three engines that I have had, only one had problems, and that was from my stupidity plus the ignition timing being WAY advanced and from the single carb and trying to run it when gas flow was obstructed. OK. So replace seats ONLY if they sit lower than the rest? I seem to recall that most of the time the seats usually just fall into the bore of the valve, not causing ultimate destruction. I feel better (IMG:style_emoticons/default/smile.gif) I guess it all comes down to this: stock or not, if the temp doesnt go well over 400F, there shouldnt be any problems. I mean if a hippie can drive a bus for many miles without major trouble, I should be able to with all of the dwell meters and timing lights and CHT guages I have, right? Right on! and far out! |
bd1308 |
Oct 17 2006, 03:15 PM
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#8
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Sir Post-a-lot Group: Members Posts: 8,020 Joined: 24-January 05 From: Louisville,KY Member No.: 3,501 |
(IMG:style_emoticons/default/smoke.gif) grooovy!
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7TPorsh |
Oct 17 2006, 03:16 PM
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#9
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7T Porsh Group: Members Posts: 2,691 Joined: 27-March 06 From: Glendale Ca Member No.: 5,782 Region Association: Southern California |
I think maybe you are too worried about dropping valve seats. I know this has happened before to you. This usually only happenes when the heads get too hot. Your first motor had that single carb and ran hot. I don't remember why the other blew. I think you just had a run of bad luck. There are an awful lot of motors out there that this hasn't and will never happen to them. Do a normal rebuild and only change the seats if necessary (cracked, badly worn or loose). I was told by the PO that I am running a 2.0 block with 1.7 heads. Didn't make sense to me; still doesn't. I too want to do something with them. |
G e o r g e |
Oct 17 2006, 03:35 PM
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#10
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Dr Group: Members Posts: 1,905 Joined: 20-September 05 From: Southern Cal Member No.: 4,832 Region Association: None |
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Jake Raby |
Oct 17 2006, 04:26 PM
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#11
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Engine Surgeon Group: Members Posts: 9,398 Joined: 31-August 03 From: Lost Member No.: 1,095 Region Association: South East States |
You should have taken advantage of Len's special product of the week from a few weeks ago.. If so for 550 bucks you'd have gotten a full rebuild including new seats,guides and the works.
BTW- Inspecting a set of heads can't be thoroughly be completed without an oven, cracks wake up at 300 degrees.. |
bd1308 |
Oct 17 2006, 04:37 PM
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#12
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Sir Post-a-lot Group: Members Posts: 8,020 Joined: 24-January 05 From: Louisville,KY Member No.: 3,501 |
sounds like a deal i missed.
but for what I was wanting to do, it would have been around 550 anyway. |
JPB |
Oct 17 2006, 04:46 PM
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#13
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The Crimson Rocket smiles in your general direction. Group: Members Posts: 2,927 Joined: 12-November 05 From: Tapmahamock, Va. Member No.: 5,107 |
(IMG:style_emoticons/default/headbang.gif) Need I say more? (IMG:style_emoticons/default/biggrin.gif)
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Jake Raby |
Oct 17 2006, 05:13 PM
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#14
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Engine Surgeon Group: Members Posts: 9,398 Joined: 31-August 03 From: Lost Member No.: 1,095 Region Association: South East States |
listening to my radio shows are the smart thing to do. 16 guys tok advantage of the deal and they got 10% off all the other valve train parts as well.. Then you have the guys that bought engine kits for up to 1200 bucks off a few weeks ago as well..
the deals will continue, just wait till I open up the "Blue light special" forum in a few days! |
bd1308 |
Oct 17 2006, 05:16 PM
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#15
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Sir Post-a-lot Group: Members Posts: 8,020 Joined: 24-January 05 From: Louisville,KY Member No.: 3,501 |
I'll just slap something together, only this time it wont already have 70k on it.
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Jake Raby |
Oct 17 2006, 05:20 PM
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#16
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Engine Surgeon Group: Members Posts: 9,398 Joined: 31-August 03 From: Lost Member No.: 1,095 Region Association: South East States |
Trusting factory valve seats is just plain dumb.
I tried to keep from being so point blank, but I have to get the point across somehow. |
bd1308 |
Oct 17 2006, 05:22 PM
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#17
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Sir Post-a-lot Group: Members Posts: 8,020 Joined: 24-January 05 From: Louisville,KY Member No.: 3,501 |
Then why are people still running on stock engines.
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Jake Raby |
Oct 17 2006, 05:38 PM
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#18
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Engine Surgeon Group: Members Posts: 9,398 Joined: 31-August 03 From: Lost Member No.: 1,095 Region Association: South East States |
Lets just say that stock seats are the only ones these days that fail.
if you see how many fall out with just having the heads flipped upside down in the oven and heated to 400F you'd never question why the seats being changed is so beneficial. Keep in mind that we are talking heads that are sitting static in the oven, without having combustion pressure or vibration assisting them... Lift off the heads and seats are laying there, right where they fell out. Stock seats that see over 400F can go at any time, some fuels and climates reduce the threshold by 50 degrees. |
bd1308 |
Oct 17 2006, 05:39 PM
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#19
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Sir Post-a-lot Group: Members Posts: 8,020 Joined: 24-January 05 From: Louisville,KY Member No.: 3,501 |
OK! This is getting retarded.
You're valve seats handle something like 1200F temps. That's awesome, and kinda scary. If I get a cool-running cam and then run a stock head BELOW 400F, I shouldnt have any problems. SO you're telling me before you came around, engines always blew up after a short amount of time and always overheated and never worked? This is intresting, because I am good friends with a VW mechanic who has put together many engines, and never did do a watercooled conversion, or told someone to kiss off because the stock stuff wasnt 'trustworthy' Am I being dumb for trusting stock seats? Maybe, or maybe I know that I need to keep an eye on my engine. Honestly Jake, do you want your engines running above 400F-500F either? Didnt think so. I'd love to have a discussion about this if I ever meet you, and if you'd like to contact me privately and request this deleted, I will. |
Jake Raby |
Oct 17 2006, 05:53 PM
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#20
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Engine Surgeon Group: Members Posts: 9,398 Joined: 31-August 03 From: Lost Member No.: 1,095 Region Association: South East States |
Its a safety factor...
The fact is the only thing that fails at 400F is the seats, and as stated they can fail at less than that due to their sintered material and the interferance fit the factory gave them THIRTY PLUS YEARS AGO!! when a seat fails it can take everything else with it, especially if the keepers and retainer pops off of the valve.. No need to delete a thread, people need to read this and they need to understand that this is the primary killer of Type 4 engines and has been since its conception. The issues can be avoided and can be done cost effectively. Keep the heads below 400F and hope that your luck holds. Since then the heads have been heat cycled millions of times... |
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