Cracker Jack Prize, engine disassembly |
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Cracker Jack Prize, engine disassembly |
r3dplanet |
Mar 29 2015, 08:56 PM
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#1
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Senior Member Group: Members Posts: 679 Joined: 3-September 05 From: Portland, Oregon Member No.: 4,741 Region Association: None |
Hello peeps.
I'm back from a long period of hibernation following my bone marrow transplant. Here's a helpful life hacking skill: do not get cancer. During the eight months I was gone, my birthday came and went. Now I'm 42. Things are much different now that I'm back on my aching feet. For example, I now spend my days playing a new mental game called "Post Transplant or Middle Age?" to explain things like my increased waistline diameter, aching muscles, slow wit, and any other number of minor grievances. Today was the first day I've done anything 914-ish in a long, long time. Since my Corvair engine project is on hold indefinitely, I've put plans into place to convert my existing 1.7 liter engine into a 1911. Before the Corvair project I had previously bought pistons, 94mm cylinders that are good enough to bore, rockers, lifters, new cam, swivel adjusters, etc. So I decided to put them to good use and rebuild my engine. Today was a lovely Spring day complete with sunny skies and cherry blossoms. So I disassembled the engine that has been languishing in the garage since last June. Guess what? My 1.7 liter engine already has 96mm pistons and cylinders. I have no idea what the crankshaft is so maybe it's a 1911 or maybe it's a 2056. I don't know. But it certainly was a surprise since the person I bought it from was convinced it was a 1.7 liter from a 1973 car. Is there some easy way to find which crankshaft I have or do I have to wait until I split the case? What I do know is that I spent two years trying in vain to get the 1.7 liter D-Jet system to work on that engine. With today's interesting discovery I know at least that I had (and rebuilt) the wrong MPS along with the wrong injectors (VW Black for 1600-1700cc) and wrong computer. Hoo-ray! Thank you so very much 20/20 hindsight! At least I know why it ran super lean all the time. I actually feel much better about the D-Jet failure now. Chances are that it all worked perfectly well after the work I put into it. It was just the wrong engine. I blame and applaud myself simultaneously. My sincere hope is that becoming concurrently post-transplant and middle aged brings newfound wisdom along with all of the extra groaning sounds I now make. How do I identify which crankshaft I have? Cam? Your pal, Marcus |
Bruce Hinds |
Mar 29 2015, 09:36 PM
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#2
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V-8 madness Group: Members Posts: 733 Joined: 27-December 06 From: Port Orchard, WA Member No.: 7,391 Region Association: Pacific Northwest |
I don't know about your cam, but welcome back! (IMG:style_emoticons/default/cheer.gif)
I'm sure you'll be wiser for the experience. |
rick 918-S |
Mar 29 2015, 09:39 PM
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#3
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Hey nice rack! -Celette Group: Members Posts: 20,417 Joined: 30-December 02 From: Now in Superior WI Member No.: 43 Region Association: Northstar Region |
Awesome Marcus! Winning! All the way around!
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Old Yella |
Mar 29 2015, 11:06 PM
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#4
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Old Yella Group: Members Posts: 158 Joined: 2-July 13 From: Canberra Australia Member No.: 16,086 Region Association: Southwest Region |
My wife is a survivor and still has all the aches and pains. I hope all goes well with your physical and mental recovery from such a shit thing to happen to you. Just plod along in the garage and enjoy yourself--sorry I can't give much advice on your engine as I'm pretty new to 914's.
Cheers and good luck with it. Regards Old Yella |
KELTY360 |
Mar 29 2015, 11:32 PM
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#5
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914 Neferati Group: Members Posts: 5,029 Joined: 31-December 05 From: Pt. Townsend, WA Member No.: 5,344 Region Association: Pacific Northwest |
I'd go with Post Transplant for now...that way you still have Middle Age to fall back on.
Glad to see you back, your Corvair thread was very interesting. One foot in front of the other.... |
falcor75 |
Mar 30 2015, 12:08 AM
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#6
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Senior Member Group: Members Posts: 1,579 Joined: 22-November 12 From: Sweden Member No.: 15,176 Region Association: Scandinavia |
Maybe I'm showing my own engineretardness here but if you have the heads off, cant you just measure the distance between a cylinder at the top of the stroke and bottom of the stroke and get the effective stroke distance....should give you a clue of what crank you have? Or maybe it doesnt work like that?
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bulitt |
Mar 30 2015, 03:03 AM
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#7
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Achtzylinder Group: Members Posts: 4,188 Joined: 2-October 11 Member No.: 13,632 Region Association: South East States |
For the cam you can put a degree wheel on the crank and a dial indicator on a pushrod. Then you can sorta figure out the lobe opening and closing. The gross lift at the cam, then multiply it by the rocker arm ratio. Blah blah...
Did I say sorta? Glad to see you back! |
Porschef |
Mar 30 2015, 04:15 AM
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#8
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How you doin' Group: Members Posts: 2,165 Joined: 7-September 10 From: LawnGuyland Member No.: 12,152 Region Association: North East States |
Great news! (IMG:style_emoticons/default/smilie_pokal.gif)
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Cap'n Krusty |
Mar 30 2015, 05:13 AM
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#9
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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 |
For the crankshaft it's less complicated. Measure the stroke (how far the piston moves from BDC to TDC. You don't even have to be that accurate, as a 1.7 has a 66mm stroke and a 2.0 has a 71mm stroke ...
The Cap'n |
wndsrfr |
Mar 30 2015, 06:42 AM
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#10
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Senior Member Group: Members Posts: 1,428 Joined: 30-April 09 From: Rescue, Virginia Member No.: 10,318 Region Association: MidAtlantic Region |
For the cam you can put a degree wheel on the crank and a dial indicator on a pushrod. Then you can sorta figure out the lobe opening and closing. The gross lift at the cam, then multiply it by the rocker arm ratio. Blah blah... Did I say sorta? Glad to see you back! (IMG:style_emoticons/default/agree.gif) I'm thinking that you can use the flywheel for a degree wheel....put a chalk mark at tdc, then at the point that the pushrod just starts to move....then with a straightedge & protractor find the angles....should be close enuf..... PS. 42....hmmmm. ..... the answer to life, the universe, and everything! |
Al Meredith |
Mar 30 2015, 08:46 AM
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#11
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Senior Member Group: Members Posts: 958 Joined: 4-November 04 From: Atlanta, ga Member No.: 3,061 |
Remove the oil pump and you should be able to see the nose of the cam. Look for a number.if the FI will not work it is probably the cam.
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McMark |
Mar 30 2015, 09:30 AM
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#12
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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 |
Welcome Back! If you've already removed pistons/cylinders and can't easily measure stroke, just measure the crank where the rod mounts. That diameter is different on the 71mm stroke than it is on the 66mm stroke cranks. Hint: That diameter is where the extra 5mm of stroke comes from.
As far as the cam, is it riveted to the cam gear? If so, it's stock. If it's bolted on, look for stampings -- especially on the face where the oil pump ties in (in the center of the cam gear). |
914_teener |
Mar 30 2015, 10:15 AM
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#13
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914 Guru Group: Members Posts: 5,194 Joined: 31-August 08 From: So. Cal Member No.: 9,489 Region Association: Southern California |
Hey welcome back. Glad you are better.
I wouldn't assume the black tipped injectors are the wrong ones. Check the numbers on them. A lot of times a re-builder will use the black pintel covers. The flow rate is what counts. Have them checked for flow and working order by a good rebuilder if you are going to keep the D-jet. And...welcome to middle age. It will instill you with grace and humility.....or...... make you grumpy as hell or both. |
r3dplanet |
Mar 30 2015, 11:38 AM
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#14
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Senior Member Group: Members Posts: 679 Joined: 3-September 05 From: Portland, Oregon Member No.: 4,741 Region Association: None |
Everyone, thanks for the well wishes! It's good to be back. I dropped by a coffee shop this morning to get some tea and a crescent roll. While staring into space I heard a couple of young gluten-frees at the table behind me explaining how much they loved classic rock. You know, like Nickelback. When I returned home I examined my vinyl record collection and sure enough almost everything there dates from 1966-1996. Middle age, you are cruel and sneaky mistress.
In retrospect, yes, it would have been easier to to measure the stroke when I still had the cylinders connected. Whoops. When I split the case I'll take measurements between the long center axis of the crankshaft and the axis of the throws. I was just hoping there would be a stamped marking of some kind. Oh - maybe the bearings will be marked. I plan to send the cam off to a good local cam grinder to have him take measurements and find out what condition it's in. I'm super curious to know which cam is in there. Meanwhile, the heads are off to Mr. Hoffman. |
relentless |
Mar 30 2015, 11:56 AM
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#15
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Member Group: Members Posts: 350 Joined: 1-April 07 From: Oregon Member No.: 7,636 |
Welcome back Marcus.
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r_towle |
Mar 30 2015, 12:15 PM
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#16
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Custom Member Group: Members Posts: 24,560 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States |
Hello peeps. I'm back from a long period of hibernation following my bone marrow transplant. Here's a helpful life hacking skill: do not get cancer. During the eight months I was gone, my birthday came and went. Now I'm 42. Things are much different now that I'm back on my aching feet. For example, I now spend my days playing a new mental game called "Post Transplant or Middle Age?" to explain things like my increased waistline diameter, aching muscles, slow wit, and any other number of minor grievances. Today was the first day I've done anything 914-ish in a long, long time. Since my Corvair engine project is on hold indefinitely, I've put plans into place to convert my existing 1.7 liter engine into a 1911. Before the Corvair project I had previously bought pistons, 94mm cylinders that are good enough to bore, rockers, lifters, new cam, swivel adjusters, etc. So I decided to put them to good use and rebuild my engine. Today was a lovely Spring day complete with sunny skies and cherry blossoms. So I disassembled the engine that has been languishing in the garage since last June. Guess what? My 1.7 liter engine already has 96mm pistons and cylinders. I have no idea what the crankshaft is so maybe it's a 1911 or maybe it's a 2056. I don't know. But it certainly was a surprise since the person I bought it from was convinced it was a 1.7 liter from a 1973 car. Is there some easy way to find which crankshaft I have or do I have to wait until I split the case? What I do know is that I spent two years trying in vain to get the 1.7 liter D-Jet system to work on that engine. With today's interesting discovery I know at least that I had (and rebuilt) the wrong MPS along with the wrong injectors (VW Black for 1600-1700cc) and wrong computer. Hoo-ray! Thank you so very much 20/20 hindsight! At least I know why it ran super lean all the time. I actually feel much better about the D-Jet failure now. Chances are that it all worked perfectly well after the work I put into it. It was just the wrong engine. I blame and applaud myself simultaneously. My sincere hope is that becoming concurrently post-transplant and middle aged brings newfound wisdom along with all of the extra groaning sounds I now make. How do I identify which crankshaft I have? Cam? Your pal, Marcus Welcome back. Not the same as you, certainly not as drastic, but after a year of abdominal surguries, multiple issues, I found that the only way to avoid the groans is the get to a gym and become in better shape than ever before... For the motor. If you pull the cylinders, check the pin height on the piston compared to the pin height on 1.7/1.8 pistons and 2.0 liter pistons. That will tell you the stroke. If you have not pulled the cylinders, measure the stroke as you rotate the engine from TDC to BDC on any cylinder. Camshaft can be measured by coming in via a lifter hole (remove push rod and tube) and setup a dial indicator that rides the lifter. You would need a degree wheel setup properly, then document when it starts the lift, and the lift height, and duration. Should be one of these (close enough) measurements to let you know if it is a stock camshaft or not. From there, if its not stock, I would open it up and do a better job of measuring,but I think its easier to measure an unknown camshaft with it installed in the case and using a degree wheel....and I would prefer to measure off the lifter to eliminate all the math.... |
r_towle |
Mar 30 2015, 12:16 PM
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#17
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Custom Member Group: Members Posts: 24,560 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States |
you will also need to verify what heads you are running by part number and valve diameter measurements so you know what you are starting with for basic design.
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