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930cabman |
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#21
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Advanced Member ![]() ![]() ![]() ![]() Group: Members Posts: 3,481 Joined: 12-November 20 From: Buffalo Member No.: 24,877 Region Association: North East States ![]() ![]() |
With what you just described, I can’t see any scenario where I wouldn’t be taking it apart. (IMG:style_emoticons/default/agree.gif) (IMG:style_emoticons/default/agree.gif) (IMG:style_emoticons/default/agree.gif) (IMG:style_emoticons/default/agree.gif) (IMG:style_emoticons/default/agree.gif) (IMG:style_emoticons/default/agree.gif) (IMG:style_emoticons/default/agree.gif) It's already OUT! With the plugs and the rockers off it should spin completely free. You should be able to turn the flywheel/front pully with a single finger and no effort. "Gripping" should not be required. You should tear down. IMO doing anything else is a waste of time. you should be able to get that down to a "short block" with the rods hanging out of the case fairly quickly. The most likely culprit IMO is a ring that got damaged during installation. Using a friend supporting the rods that should "free wheel" with zero drag. During the tear down you should verify both bore and stroke. The 44s it came with should be on a BIG motor, not a small one. Ordered borescope today to look inside cylinders through spark plug holes. Hope to learn more about which pistons were installed (part numbers from tops) and better idea of valves and heads. From there I hope to decide whether to pull the heads for a better look. I”ll probably try to measure piston travel and valve lift too. Would be nice to know a bit more about what I’ve got before trying to start. The fan is very close to the case. Seems like it might be touching a little as I spin the motor by hand. It’s so pretty with the tin and case powder coated. Hope I don’t have to tear it down too far if at all. Will post what I find with the scope. Might even figure out how to take pictures. Are you able to get her to spin reasonably easy? if so, you might be on your way. Fan will be close to the housing, perhaps a special washer was not installed. Yes it spins fairly easy by pushing the fan by hand. Just remembered Jake Raby advice on loosening the oil filter when cranking the engine to purge air out of the oil passages so oil pressure can be established. Might give that a try while waiting for the boroscope to arrive. If valve/piston clearance looks ok with boroscope I will likely put the push rods and rockers back on. And check with boroscope with valves opening. Then loosen tappets to reset valve clearance and measure cam lobe height by measuring push rod travel from valve closed to valve open. Will also measure piston travel to learn what crank I have. And check compression. Anything questionable and I’ll tear it down to inspect. The motor was built over 10 yrs ago by a supposed “race engine guy” but no records. It looks nice and turns over well by hand and with starter without the rockers installed. All good news, you may have a winner. Always good to check things out, but it's possible to assemble the beast and she will run. FI or carbs? Weber 44s. I have all the FI stuff from 73 and a complete 74 1.8 parts car. Will see if the webers are fun and tunable. 44's might be a bit big, depending on cc's, CR, cam, .... I tried 44's on a 2056 build and I was unable to get a good vacuum signal. Wound up with 40's and couldn't be happier |
Robroe |
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#22
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Member ![]() ![]() Group: Members Posts: 76 Joined: 10-August 21 From: Wenatchee, WA Member No.: 25,793 Region Association: Pacific Northwest ![]() |
Hopefully it was just crazy compression and stiff springs.... Just measured stroke by inserting a rubber hose in the plug hole and turning engine by hand from bottom of piston stroke to top. It measured 3.95 inches stroke. That seems big compared to stock published stroke at 2.66 inches stroke. Is 3.95” stroke possible with a non stock crank? This is supposed to be a hot engine but adding 1.3” to stroke seems like a lot. Turns easy by hand now so loosening up. |
emerygt350 |
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#23
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Advanced Member ![]() ![]() ![]() ![]() Group: Members Posts: 2,385 Joined: 20-July 21 From: Upstate, NY Member No.: 25,740 Region Association: North East States ![]() |
Wow, if that is right it is a monster. If you have 96mm pistons and your number is correct for stroke you would have a 2.8 liter. I suspect it would eat itself. With 93s it's still a 2.7
And those 44s make sense with that. |
930cabman |
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#24
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Advanced Member ![]() ![]() ![]() ![]() Group: Members Posts: 3,481 Joined: 12-November 20 From: Buffalo Member No.: 24,877 Region Association: North East States ![]() ![]() |
Hopefully it was just crazy compression and stiff springs.... Just measured stroke by inserting a rubber hose in the plug hole and turning engine by hand from bottom of piston stroke to top. It measured 3.95 inches stroke. That seems big compared to stock published stroke at 2.66 inches stroke. Is 3.95” stroke possible with a non stock crank? This is supposed to be a hot engine but adding 1.3” to stroke seems like a lot. Turns easy by hand now so loosening up. Could be a beast (IMG:style_emoticons/default/piratenanner.gif) Assuming the heads are still bolted in place and spinning freely, is it an option to put fire in those combustion chambers? |
Robroe |
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#25
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Member ![]() ![]() Group: Members Posts: 76 Joined: 10-August 21 From: Wenatchee, WA Member No.: 25,793 Region Association: Pacific Northwest ![]() |
Just remeasured stroke using plastic straw. 3.8” which is 96mm. Haven’t seen cranks for sale bigger than 86mm stroke. So not sure what I’ve got. Looking forward to boroscope viewing to see if I can read part numbers on to of pistons. Might be able to tell if the are 96mm or 94 mm and even see the valves without dismantling it. The heads are supposed to be special, but we shall see.
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Robroe |
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#26
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Member ![]() ![]() Group: Members Posts: 76 Joined: 10-August 21 From: Wenatchee, WA Member No.: 25,793 Region Association: Pacific Northwest ![]() |
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emerygt350 |
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#27
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Advanced Member ![]() ![]() ![]() ![]() Group: Members Posts: 2,385 Joined: 20-July 21 From: Upstate, NY Member No.: 25,740 Region Association: North East States ![]() |
They look like my 96mm pistons. If that thing is as big as it seems I hope they are forged....
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Superhawk996 |
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#28
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914 Guru ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 6,419 Joined: 25-August 18 From: Woods of N. Idaho Member No.: 22,428 Region Association: Galt's Gulch ![]() ![]() |
With respect to stroke - you’re neglecting that the spark plug isn’t perpendicular to the piston. What you’re measuring isn’t 1:1
Given that none of this is stock 1.7L I’d be taking that apart to figure out exactly what is in there and how it was built. There are plenty of stroker cranks that require clearance work be done to the case. Likewise those relief cuts in pistons may not be clearing valves properly. |
emerygt350 |
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#29
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Advanced Member ![]() ![]() ![]() ![]() Group: Members Posts: 2,385 Joined: 20-July 21 From: Upstate, NY Member No.: 25,740 Region Association: North East States ![]() |
As long as the tip of the probe isn't sliding the distance will not be altered if it isn't perfectly perpendicular.
I think it's worth pulling the heads at this point just to figure out what the compression is. If this is a 2.7 you are going to have to be careful. If the bottom end is rotating freely I wouldn't go deeper. But that's me. |
Superhawk996 |
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#30
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914 Guru ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 6,419 Joined: 25-August 18 From: Woods of N. Idaho Member No.: 22,428 Region Association: Galt's Gulch ![]() ![]() |
Dude not even close to perpendicular to the dome of the piston. Especially on 1.7L heads. I don’t have a set of heads in front of me to measure but probably almost 45 degrees on 1.7L heads.
Geometry matters. ![]() |
Robroe |
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#31
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Member ![]() ![]() Group: Members Posts: 76 Joined: 10-August 21 From: Wenatchee, WA Member No.: 25,793 Region Association: Pacific Northwest ![]() |
As long as the tip of the probe isn't sliding the distance will not be altered if it isn't perfectly perpendicular. I think it's worth pulling the heads at this point just to figure out what the compression is. If this is a 2.7 you are going to have to be careful. If the bottom end is rotating freely I wouldn't go deeper. But that's me. Ok. Pulling the heads is recommended. What am I looking for/measuring when I pull them? Should I install any new gaskets? It never run so all new inside but been sitting for 10 years without oil in climate control. Anything I need to do when pulling heads? |
Superhawk996 |
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#32
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914 Guru ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 6,419 Joined: 25-August 18 From: Woods of N. Idaho Member No.: 22,428 Region Association: Galt's Gulch ![]() ![]() |
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Superhawk996 |
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#33
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914 Guru ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 6,419 Joined: 25-August 18 From: Woods of N. Idaho Member No.: 22,428 Region Association: Galt's Gulch ![]() ![]() |
You need to know the stroke, then you can determine displacement.
You need to know the compression ratio. You need to know the deck height. Since it won’t turn over by hand with the rockers on it you need to determine what valve lifts you’re dealing with and whether you have adequate valve clearance to the piston. The pocketed pistons are a whole other story. Who’s pistons? How much material is left in the piston dome? You need to figure out if it was put together with head gaskets and get rid of them if it was. Pay particular attention to Jake Raby’s posts to this link. I know this link refers to 2.0L but it pertains to all displacements. http://www.914world.com/bbs2/index.php?sho...70781&st=40 Be aware that rubber ages and hardens regardless of whether it was in climate control or not. You should be checking crank end play. There are literally dozens of things that should be verified rather than just hoping it was put together properly and won’t grenade when you run it. |
930cabman |
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#34
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Advanced Member ![]() ![]() ![]() ![]() Group: Members Posts: 3,481 Joined: 12-November 20 From: Buffalo Member No.: 24,877 Region Association: North East States ![]() ![]() |
There are literally dozens of things that should be verified rather than just hoping it was put together properly and won’t grenade when you run it. (IMG:style_emoticons/default/agree.gif) probably best to open her up all the way and confirm exactly what you have instead of risking damage of new parts |
emerygt350 |
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#35
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Advanced Member ![]() ![]() ![]() ![]() Group: Members Posts: 2,385 Joined: 20-July 21 From: Upstate, NY Member No.: 25,740 Region Association: North East States ![]() |
Or you could continue to determine if in fact you do have contact (I am personally doubting it) first. Send us pics of the heads, I doubt they are 1.7 heads, but they could be. Do the plugs come in from the top of the motor? Are there 3 or four bolts holding the intakes on?
If it is not valve contact but instead spring strength, it's your call. I would pull a head to determine compression and measure valve diameter. If they were building a beast I would hope they put big valves in it. As superhawk mentioned, no gaskets to worry about, however there may be shims under the jug. Nice thing is you will be able to verify how much distance you have between the piston and valves and set your own compression. That book is a good one and worth having on the shelf. And raby is raby of course. |
technicalninja |
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#36
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Senior Member ![]() ![]() ![]() Group: Members Posts: 1,807 Joined: 31-January 23 From: Granbury Texas Member No.: 27,135 Region Association: Southwest Region ![]() ![]() |
I DON"T like the raised 95.95.
I want the tops of my pistons smooth as a "baby's ass" The valve reliefs look rough too. Look like inexpensive forged to me. I'd fully tear down. Remove heads, lock jugs in case with crossbars (you can use wood here, just trying to lock jugs to case) check deck heights and stroke. Now you know how big it is... If it's a stroker (more than 71) I'd fully tear down because of it. Strokers REQUIRE special tricks for clearance of the crank/rods/camshaft and are a significant increase in complexity for the builder. If it comes out stock 2.0l (71) I might check "feel" of the assembly and re-assemble. If you have a stroker there you hit the jackpot! I'd LOVE to "find" a 78mm stroke with flat tops at 96mm bore. That is a 2255 and is a VERY GOOD combo to have. Take pictures and post on here. You will get opinions, lots of opinions... |
technicalninja |
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#37
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Senior Member ![]() ![]() ![]() Group: Members Posts: 1,807 Joined: 31-January 23 From: Granbury Texas Member No.: 27,135 Region Association: Southwest Region ![]() ![]() |
Tear down tip!
Keep everything in its originally installed position. I even watch the hardware for placement and direction/clocking. All the crap should be "indexed". If the lifters have ever run, they HAVE to stay on their respective cam lobes! When you're taking the dash out of a Prius (I know you're not doing this) the placement of every single screw is important. Put a long one where a short one should have gone and you can pierce an ECU. I once saw a 300ZX twin turbo PCM destroyed by a screw the owner put in the wrong place. $1800 mistake in 1998! Fastner placement can be CRITICAL I'll often use egg containers, biscuit pans to keep track of hardware. |
Jack Standz |
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#38
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Member ![]() ![]() Group: Members Posts: 353 Joined: 15-November 19 From: Happy Place (& surrounding area) Member No.: 23,644 Region Association: None ![]() |
U can tell it's a stroker if you can see spacers under the cylinders. Maybe take a look with that scope/camera through the sparkplug hole in the tin? My guess is that you're looking at a 2056 (possibly a 1911).
Yes, check everything. Although not likely, make sure the valve reliefs on the pistons (probably cast) aren't upside-down, because that would be a bummer. Measure and write down all the speciations because you will not remember. Things like bore, stroke, valve sizes, intake and exhaust lift or cam number if there is one, blueprint the oil pump, plug the oil gallerys with tapered threaded plugs, etc., etc. While you have it apart, lubricate it properly and get ready for startup, especiallythe special lube on the cam lobes. We also had a 2056 project motor that was stalled and sat for over 10 years. When we got back to the project, the molly-lube turned into a grey stiff gunk. Cleaned things up and started again with new bearings, etc. BTW you can turn the motor over with a 23mm(?) wrench on the alternator pulley fastener if the alternator belt isn't too loose (you can squeeze the belt with your hand while turning the bolt to help stop any slipping). Just don't force anything if you feel resistance. Best wishes for a successful startup! |
Robroe |
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#39
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Member ![]() ![]() Group: Members Posts: 76 Joined: 10-August 21 From: Wenatchee, WA Member No.: 25,793 Region Association: Pacific Northwest ![]() |
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Robroe |
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#40
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Member ![]() ![]() Group: Members Posts: 76 Joined: 10-August 21 From: Wenatchee, WA Member No.: 25,793 Region Association: Pacific Northwest ![]() |
If I’m going to tear this engine down to inspect, a proper engine stand would probably easier than the home made test start stand it’s on now. What engine stands do y’all prefer?
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