Head Gaskets |
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Head Gaskets |
brandomc |
Sep 16 2009, 04:48 PM
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#1
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Member Group: Members Posts: 113 Joined: 14-May 09 From: los angeles california Member No.: 10,363 Region Association: Southern California |
I bought a engine last week that was supposedly a 1.7, but the guy didnt really know for sure. After looking at the case numbers, I think it might be a 1.8?? It starts with EB. I took all of the sheetmetal off to repaint it, and everything is really clean accept for around 1 of the cylinders between the head and the cylinder, it is black and kindof oily. I figure this is a leaky cylinder. Do i need new head gaskets? Or just retorque the head? Where do i get head gaskets? Pelican parts doesnt sell them. What should i do with this? It is supposed to be a fairly low mileage engine. Thanks
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southernmost914 |
Sep 16 2009, 05:00 PM
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#2
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KEY WEST/HAVANA Tunnel Authority Group: Members Posts: 338 Joined: 16-October 07 From: Key West/ St. Augie, Fl USA Member No.: 8,234 Region Association: South East States |
EB is a 1973 1.7 Calif. motor according to my books. (IMG:style_emoticons/default/bye1.gif)
Steve |
VaccaRabite |
Sep 16 2009, 05:06 PM
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#3
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En Garde! Group: Admin Posts: 13,553 Joined: 15-December 03 From: Dallastown, PA Member No.: 1,435 Region Association: MidAtlantic Region |
It is surely a leak. If you did a compression and a leakdown test, you would likely find that cylinder to be leaky. Now go do compression (at least) and leakdown and report back
If you want to find a stop gap that MIGHT work, check the torque on the head. Maybe it is a little loose. If it is not loose, overtightening by a pound or two might close it up. This won't be a longtime fix, and I'll probably get flamed for suggesting it. But it can work for a while. Head gaskets were often removed and not replaced due to a tech note by VW for the T4 in the Bus. You engine may not have head gaskets at all. So - here are some of the possible causes for a head leak at the cylinder. 1) loose bolts. This is what you are hoping for. 2) blown head gasket (expect enthusiastic debate on the value of head gaskets - I don't run one in my car. Others do.) 3) Case at the base of the cylinders is collapsing. (rebuild time) 4) worn/cracked head 5) worn/cracked cylinder 6) any combination of the above, and other stuff that was not on the top of my head. Every used motor should be treated as a rebuildable core. Even the "great condition, low mileage" ones. Especially them, actually. (IMG:style_emoticons/default/smile.gif) Zach |
brandomc |
Sep 16 2009, 05:12 PM
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#4
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Member Group: Members Posts: 113 Joined: 14-May 09 From: los angeles california Member No.: 10,363 Region Association: Southern California |
It is surely a leak. If you did a compression and a leakdown test, you would likely find that cylinder to be leaky. Now go do compression (at least) and leakdown and report back If you want to find a stop gap that MIGHT work, check the torque on the head. Maybe it is a little loose. If it is not loose, overtightening by a pound or two might close it up. This won't be a longtime fix, and I'll probably get flamed for suggesting it. But it can work for a while. Head gaskets were often removed and not replaced due to a tech note by VW for the T4 in the Bus. You engine may not have head gaskets at all. So - here are some of the possible causes for a head leak at the cylinder. 1) loose bolts. This is what you are hoping for. 2) blown head gasket (expect enthusiastic debate on the value of head gaskets - I don't run one in my car. Others do.) 3) Case at the base of the cylinders is collapsing. (rebuild time) 4) worn/cracked head 5) worn/cracked cylinder 6) any combination of the above, and other stuff that was not on the top of my head. Every used motor should be treated as a rebuildable core. Even the "great condition, low mileage" ones. Especially them, actually. (IMG:style_emoticons/default/smile.gif) Zach So, it sounds like i shoud take the head off and inspect. Is that what you would reccomend? If i do that then do i need new gaskets, or are they reuseable? Sorry if these questions sound stupid, just new to air cooled motors. What would need to be done to the engine to remove the gaskets and get everything to seal back up without them? |
aircooledtechguy |
Sep 16 2009, 05:13 PM
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#5
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The Aircooledtech Guy Group: Members Posts: 1,966 Joined: 8-November 08 From: Anacortes, WA Member No.: 9,730 Region Association: Pacific Northwest |
I would pull the head and see if there is a gasket in there that is getting sucked inward. If there is remove it AND the other three from the other cylinders. Check that head for erosion at the leaking point. These leaks when caught early are no problem to correct. Over time the leak acts like a cutting torch to totally destroy the head and piston.
These gaskets PROMOTE leaks and should NOT be used. |
brandomc |
Sep 16 2009, 05:21 PM
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#6
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Member Group: Members Posts: 113 Joined: 14-May 09 From: los angeles california Member No.: 10,363 Region Association: Southern California |
I would pull the head and see if there is a gasket in there that is getting sucked inward. If there is remove it AND the other three from the other cylinders. Check that head for erosion at the leaking point. These leaks when caught early are no problem to correct. Over time the leak acts like a cutting torch to totally destroy the head and piston. These gaskets PROMOTE leaks and should NOT be used. Thanks for the info, that sounds like a good solution. Does everybody else agree? Is removing that gasket going to bump up my compression ratio at all? Just currious. What can i do if ther is some surface erosion? Is everything going to bolt right back on, or do i need any other seals or caskets when i go through this? Thanks again |
VaccaRabite |
Sep 16 2009, 05:25 PM
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#7
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En Garde! Group: Admin Posts: 13,553 Joined: 15-December 03 From: Dallastown, PA Member No.: 1,435 Region Association: MidAtlantic Region |
So, it sounds like i shoud take the head off and inspect. Is that what you would reccomend? If i do that then do i need new gaskets, or are they reuseable? Sorry if these questions sound stupid, just new to air cooled motors. What would need to be done to the engine to remove the gaskets and get everything to seal back up without them? No, I'd recommend doing compression and leakdown testing on all cylinders, even if you have to do it cold because you can't start the engine right now. That will at least give you a ball park on what you have got. Compression testers are cheap at any FLAPS (Friendly Local Auto Parts Store). You can usually borrow a leak down tester from Autozone or Advance, and rent them sometimes from Napa. You need a source of compressed air though. Once done, report back on your findings. be sure to note is the testing was done on a warm or cold engine. Be sure that the throttle is wide open when doing compression testing. If possible, run the engine on a pallet or test stand to get it warm. if not, do it cold (your numbers will be a little lower). If you remove the heads, be VERY CAREFUL to keep each lifter and pushrod together. They need to go back into the same bore they came out of. Even if you are or are not using head gaskets, you want the tops of each cylinder to be as close to the same height as possible. You can test this by measureing deck height, and adding shims to the bottom of the cylinder to even it out. You want all 4 the same, or as close as you can possibly get. Go to Amazon and get John Muirs book How to Keep Your AirCooled Vw Alive, and the Haynes Tech Manual for the 914. Zach |
brandomc |
Sep 16 2009, 05:33 PM
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#8
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Member Group: Members Posts: 113 Joined: 14-May 09 From: los angeles california Member No.: 10,363 Region Association: Southern California |
So, it sounds like i shoud take the head off and inspect. Is that what you would reccomend? If i do that then do i need new gaskets, or are they reuseable? Sorry if these questions sound stupid, just new to air cooled motors. What would need to be done to the engine to remove the gaskets and get everything to seal back up without them? No, I'd recommend doing compression and leakdown testing on all cylinders, even if you have to do it cold because you can't start the engine right now. That will at least give you a ball park on what you have got. Compression testers are cheap at any FLAPS (Friendly Local Auto Parts Store). You can usually borrow a leak down tester from Autozone or Advance, and rent them sometimes from Napa. You need a source of compressed air though. Once done, report back on your findings. be sure to note is the testing was done on a warm or cold engine. Be sure that the throttle is wide open when doing compression testing. If possible, run the engine on a pallet or test stand to get it warm. if not, do it cold (your numbers will be a little lower). If you remove the heads, be VERY CAREFUL to keep each lifter and pushrod together. They need to go back into the same bore they came out of. Even if you are or are not using head gaskets, you want the tops of each cylinder to be as close to the same height as possible. You can test this by measureing deck height, and adding shims to the bottom of the cylinder to even it out. You want all 4 the same, or as close as you can possibly get. Go to Amazon and get John Muirs book How to Keep Your AirCooled Vw Alive, and the Haynes Tech Manual for the 914. Zach I Dont have any way to do a compression test, the engine is not attatched to a transmission. Could i just do a leak down, then retorque the heads and see if there is a change? |
r_towle |
Sep 16 2009, 05:50 PM
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#9
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Custom Member Group: Members Posts: 24,624 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States |
If you have head gaskets, removing them will raise your compression ratio and may possibly make it so you need to run race fuel.
If the motor was built with a head gasket, remove the head, get new head gaskets and put it back together. This is a few hours of work considering its all open at this point. Do not just remove the head gaskets without measuring and knowing what you are going to end up with for your compression ratio. Head gaskets seem to have been a problem with the 2.0 liter heads due to the thinner contact sealing area. I have two motors with head gaskets, a 1.7 and a 1.8...they are fine. Rich |
VaccaRabite |
Sep 16 2009, 05:54 PM
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#10
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En Garde! Group: Admin Posts: 13,553 Joined: 15-December 03 From: Dallastown, PA Member No.: 1,435 Region Association: MidAtlantic Region |
Well, yes. In theory.
But, you are in LA. probably 25% of the membership of this board are your neighbors. Ask, offer food and brew, and you will get LOTS of help at your doorstep. Don't be shy. Zach |
brandomc |
Sep 16 2009, 06:14 PM
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#11
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Member Group: Members Posts: 113 Joined: 14-May 09 From: los angeles california Member No.: 10,363 Region Association: Southern California |
Back to the begining; where can i get head gaskets??? None of our 914 suppliers seem to sell them.
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VaccaRabite |
Sep 16 2009, 06:19 PM
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#12
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En Garde! Group: Admin Posts: 13,553 Joined: 15-December 03 From: Dallastown, PA Member No.: 1,435 Region Association: MidAtlantic Region |
Auto Atlanta, GPR, pm Capt. Krusty for them.
Zach |
McMark |
Sep 16 2009, 06:20 PM
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#13
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914 Freak! Group: Retired Admin Posts: 20,179 Joined: 13-March 03 From: Grand Rapids, MI Member No.: 419 Region Association: None |
If you insist on running them (WHY?) I probably have them here. PM me the size of the opening in the head.
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brandomc |
Sep 16 2009, 06:26 PM
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#14
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Member Group: Members Posts: 113 Joined: 14-May 09 From: los angeles california Member No.: 10,363 Region Association: Southern California |
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Cap'n Krusty |
Sep 16 2009, 06:27 PM
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#15
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Cap'n Krusty Group: Members Posts: 10,794 Joined: 24-June 04 From: Santa Maria, CA Member No.: 2,246 Region Association: Central California |
I would pull the head and see if there is a gasket in there that is getting sucked inward. If there is remove it AND the other three from the other cylinders. Check that head for erosion at the leaking point. These leaks when caught early are no problem to correct. Over time the leak acts like a cutting torch to totally destroy the head and piston. These gaskets PROMOTE leaks and should NOT be used. Thanks for the info, that sounds like a good solution. Does everybody else agree? Is removing that gasket going to bump up my compression ratio at all? Just curious. What can i do if there is some surface erosion? Is everything going to bolt right back on, or do i need any other seals or gaskets when i go through this? Thanks again I DO NOT agree. 36 Years of T4 experience, all of it professionally, tells me you need to use/keep the head gaskets on a stockish 1.7. If you choose to delete them, be sure to calculate and shim the cylinders to make up for the increased compression, something you DO NOT want, especially with the fuel we get today...... If you have erosion on either the cylinders or the heads, you'll need to replace the pistons and cylinders or surface the heads, which ever is appropriate, and shim the cylinders to compensate for the material removed. DO NOT lap the cylinders into the heads. Your eyes and arms DO NOT constitute a vertical milling machine, and they're not gonna maintain the tolerances. You will need head gaskets, pushrod tube gaskets, exhaust gaskets, valve cover gaskets, and intake insulator/gaskets. The Cap'n |
brandomc |
Sep 17 2009, 10:32 AM
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#16
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Member Group: Members Posts: 113 Joined: 14-May 09 From: los angeles california Member No.: 10,363 Region Association: Southern California |
So last night i ran a leak down test on this 1.7, and it wasn't good. Every cylinder was in the bad range accept for one in the moderate. I also did a leakdown test on the 2.0 that i picked up last week; the one that was "rebuilt" and never ran. That engine didnt test very well either. Looking in the ports, it does look like the heads were gone through, but i suspect the engine sat for a long time. Is is normal to get very much leakage through the valves when the engine is cold??
Im stuck now. I wanted this 1.7 to go into my car with little effort so that i could put all my thought into the 2.0. Now it is looking like they might both need alot of work, so maybe i should dump the 1.7 and just focus on the 2ltr? Any input on this guys? Thanks |
aircooledtechguy |
Sep 17 2009, 11:11 AM
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#17
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The Aircooledtech Guy Group: Members Posts: 1,966 Joined: 8-November 08 From: Anacortes, WA Member No.: 9,730 Region Association: Pacific Northwest |
I DO NOT agree. 36 Years of T4 experience, all of it professionally, tells me you need to use/keep the head gaskets on a stockish 1.7. I'm not trying to get into a pissing contest here, but. . . While lack about 10 years of your experience, I have seen on just about every type-4 motor I've disassembled, the head gaskets are either on their way to causing a leak (by being sucked inward) or leaking because of these gaskets. Here is a link to the VW tech bulletin that was issued regarding the use, or should I say halting the use of head gaskets on type-4 motors. VW Tech Bulletin - Head Gasket Removal & Rod Modification If you choose to delete them, be sure to calculate and shim the cylinders to make up for the increased compression, something you DO NOT want, especially with the fuel we get today...... This is also covered in the bulletin and I agree that if you remove the gaskets, you should also recalculate your static CR with out the gasket to see where it is and if necessary, add a shim under the cylinder to re-lower the CR to your desired level. However, keeping the CR as low as the factory did on these motors will not always be of benefit. The stock CR was extremely low and even with today's fuels, the added bump of shim removal will normally help the motor by increasing it's efficiency. I personally never build a motor these days below 8.0:1 - 8.5:1 for a light performance car. This is what my experience tells me. But that's just me. . . |
McMark |
Sep 17 2009, 11:36 AM
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#18
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914 Freak! Group: Retired Admin Posts: 20,179 Joined: 13-March 03 From: Grand Rapids, MI Member No.: 419 Region Association: None |
The EB motor is the lowest compression 1.7, too. It's 7.3:1 and 72hp, whereas all the other 1.7s are 8.2:1 and 80hp.
If you want to quickly boost the compression on an old motor, pull the heads, pistons and cylinders. Have the valves ground on the heads and the sealing/mating surface trued. Have the cylinders honed and get a new set of rings for the pistons. Reassemble without the head gaskets (IMHO) and you should have good compression as long as the cam is not too far gone. BUT, the above is not a real rebuild and you are spending money to buy some time. Dropped valve seats are still a real possibility that can wipe out every penny you spent doing the above. It's a gamble, but it'll get you on the road. |
VaccaRabite |
Sep 17 2009, 07:47 PM
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#19
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En Garde! Group: Admin Posts: 13,553 Joined: 15-December 03 From: Dallastown, PA Member No.: 1,435 Region Association: MidAtlantic Region |
What were the values that you were getting on the leak down? Remember they will be a little low due to the engine not being warmed up.
Tell you what I would do. Stick it in the car and run it till it breaks. Put your effort into the 2.0, and get it built ASAP. Don't put any money into the 1.7 that you can avoid. it will get the car on the road and if it only lasts a season, who cares. If it still runs when you pull it, sell it to someone else. Zach |
brandomc |
Sep 18 2009, 10:43 AM
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#20
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Member Group: Members Posts: 113 Joined: 14-May 09 From: los angeles california Member No.: 10,363 Region Association: Southern California |
What were the values that you were getting on the leak down? Remember they will be a little low due to the engine not being warmed up. Tell you what I would do. Stick it in the car and run it till it breaks. Put your effort into the 2.0, and get it built ASAP. Don't put any money into the 1.7 that you can avoid. it will get the car on the road and if it only lasts a season, who cares. If it still runs when you pull it, sell it to someone else. Zach Thats what some of my other mechanic friends said to do also, so im going to try that. Its not like it is that hard to pull these engines out, so its worth a try. The numbers on the leakdown were in the 80% leakage range. It was hissing out the valves really bad. Once the motor runs and warms up a bit, hopefully they will seat better. Yeah, i want to focus my time and money on the 2.0 and build a 2056 or something bigger maybe. |
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