engine timing rehash for the weak minded |
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engine timing rehash for the weak minded |
r3dplanet |
Jul 12 2021, 04:53 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 |
Hi everyone.
Three years ago I had a local shop rebuild my 1.7 liter engine as a 1911cc engine with parts I supplied. They did a horrible job. After getting the engine on a stand with a test rig I could start it but it ran terribly. Then I noticed the giant pools of oil under the engine. Pissed, I shelved it until now. The rebuilder pulled the freeze plugs and replaced them all with pipe fitting plugs. And every one of them was leaking. So a friend of mine came over and we tore everything down to the long block. We pulled and sealed the pipe fittings and replaced the pushrod tube seals. Now it leaks much less. But it still drips. Today we installed a 123Ignition and it failed to start. So we replaced it with the distributor I was using. It's a 022 905 205AA unit. It uses a Compufire electronic ignition module. The fuel system is twin Dellorto 36 DRLA carbs. So it won't start. It tries and then blows a flame out of one of the cylinders. Or it sputters for a few seconds and dies. Going from the beginning here's what I've done: 1. Put a bore scope into cylinder #1 and rotated the engine until the piston stops. 2. Noted that at position the timing mark on the fan is at the "0" mark. 3. The rotor is pointing directly at the spark plug wire for #1. 4. The distributor gear is correctly slotted at 12* and not 180 out No joy. A week ago I ran it just like it is but it ran terribly. I'm about five seconds from scrapping the engine. It doesn't help that the meds I take make me very confused so I'm fighting a ton of haze trying to understand what's happening. One question to start: when the distributor gear is in place am I clocking it to 12* at the fan timing mark at the "0" position or the static timing mark (|)? help thanks |
Nogoodwithusernames |
Jul 12 2021, 05:25 PM
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#2
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Member Group: Members Posts: 277 Joined: 31-May 16 From: Sutter, CA Member No.: 20,051 Region Association: None |
Spark plug wires crossed? I assume you checked they're in order but it wasn't in your list of what's done so may as well start with something easy.
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Olympic 914 |
Jul 12 2021, 06:22 PM
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#3
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Group: Members Posts: 1,709 Joined: 7-July 11 From: Pittsburgh PA Member No.: 13,287 Region Association: North East States |
Did you check that both valves are closed when the piston is at TDC?
Simple to pull the valve cover and check. The builder may have installed the gear 180 out. |
r3dplanet |
Jul 12 2021, 08:10 PM
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#4
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Senior Member Group: Members Posts: 679 Joined: 3-September 05 From: Portland, Oregon Member No.: 4,741 Region Association: None |
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r3dplanet |
Jul 12 2021, 08:11 PM
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#5
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Senior Member Group: Members Posts: 679 Joined: 3-September 05 From: Portland, Oregon Member No.: 4,741 Region Association: None |
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barefoot |
Jul 13 2021, 07:21 AM
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#6
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Senior Member Group: Members Posts: 1,334 Joined: 19-March 13 From: Charleston SC Member No.: 15,673 Region Association: South East States |
Did you check that both valves are closed when the piston is at TDC? Simple to pull the valve cover and check. The builder may have installed the gear 180 out. That's a good thought. I'll pop off the valve cover and have a look. If it runs very poorly, doesn't sound like you're 180 out, i had big problems with carburation, spitting out and would not idle. Had to send it to someone who knows the things, then ran fine. Are the cards re-built ? |
r3dplanet |
Jul 13 2021, 10:18 PM
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#7
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Senior Member Group: Members Posts: 679 Joined: 3-September 05 From: Portland, Oregon Member No.: 4,741 Region Association: None |
Yes, the carbs are rebuild and ran great a few weeks ago. Not sync'd yet but idling very well.
Here are some photos. I'm still not sure if if the cam gear orientation is correct or if I'm supposed to be using the "0" or "|" static timing mark to clock the distributor gear. The Haynes manual says to use the "0" mark but that presupposes a fuel-injected system. It says to use the "|" mark for the 1.8 liter engines. I don't know why the difference. The rotor is pointing to 10 or 11 o'clock. -m. |
Porschef |
Jul 14 2021, 04:26 AM
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#8
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How you doin' Group: Members Posts: 2,180 Joined: 7-September 10 From: LawnGuyland Member No.: 12,152 Region Association: North East States |
Glad to see you’re up and about! Awesome (IMG:style_emoticons/default/beerchug.gif)
I’m sure you’ll figger it out (IMG:style_emoticons/default/smile.gif) |
r3dplanet |
Jul 14 2021, 02:10 PM
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#9
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Senior Member Group: Members Posts: 679 Joined: 3-September 05 From: Portland, Oregon Member No.: 4,741 Region Association: None |
Glad to see you’re up and about! Awesome (IMG:style_emoticons/default/beerchug.gif) I’m sure you’ll figger it out (IMG:style_emoticons/default/smile.gif) Hi! I'm in terrible shape I'm afraid to say. In hospice now. The drugs are killing me. Plus cognitive trouble. That's why simple problems like this one have become extremely confusing. It's maddening. I've done this exact procedure fifty times but now it might as well be particle physics. |
r3dplanet |
Jul 15 2021, 07:34 PM
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#10
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Senior Member Group: Members Posts: 679 Joined: 3-September 05 From: Portland, Oregon Member No.: 4,741 Region Association: None |
Pretty much resolved. It turns out that I wasn't making any mistakes.
It was both of my fancy distributors at fault. I had been using a 205AA distributor with a Compufire ignition. I pulled it to the bench and discovered that the magnetic pickup wheel had zero clearance to the sensor. That rubbed away the top surface of the sensor. I wish to beans I had known about using a Type-3 rotor before. Would be nice if the instructions mentioned that minor factoid. Upon initial installation there was enough clearance but over time the magnetic disc wheel lost it's grip and was able to slide down the shaft, hitting the sensor. Also in my collection is a 123Ignition w/Bluetooth. What I think is out of the box that distributor has no initial tune so it just sputters and fails. Naturally my phone refuses to see the distributor via Bluetooth because Bluetooth absolutely sucks. My Thinkpad recognizes the 123tune Bluetooth connection, but the Windows software only works with the USB version, not the Bluetooth version. I'm not about to buy a whole new phone or tablet just to use this distributor so I'll put it up for sale if someone wants a deal. I already ordered the basic version of the 123Ignition as a replacement. In the meantime I robbed the 009 + Pertronix Ignitor II from my Beetle and that allowed the 914 engine to fire right up. With that I can at least perform an initial tune and sync the Dellortos. |
rhodyguy |
Jul 16 2021, 11:34 AM
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#11
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Chimp Sanctuary NW. Check it out. Group: Members Posts: 22,193 Joined: 2-March 03 From: Orion's Bell. The BELL! Member No.: 378 Region Association: Galt's Gulch |
It runs with old school points that require a feeler gauge. Carry on.
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