Fresh 2.7, doesn't want to wake up Options

[technicalninja]

Running the compression test WILL verify cam timing!
Sort of...

The thing that most effects compression test readings is intake valve closure.

If you have a cam timing screw up on one side, you WILL have similar compression readings per bank but the readings between the two banks will differ.

Driver side all read 190 and passenger side all read 145 you have a cam timing issue.

It's also the reason I mentioned checking valve adjustment before tear down.

The valves adjusted incorrectly will vary compression readings although not nearly as much as the cam timing being out.

Have you done a compression test yet?

I just love the offset cam timing holes like the 911 has. You can alter your cam timing without having to buy special gears or strange "offset" bushings.
That set up is "completely adjustable" cam timing from the factory!
It requires that the technician fully understands what he's doing but is "THE WAY" in my book for adjustable cam timing. They all aught to be like that!

[flyer86d]

I had the same issue with the 2.7 that I put together for my 68 911. I did all of the compression, spark, fuel verification. There were two issues. I was trying to run the 2.7 without a CDI box and fuel pressure was too high. I thought, they used to sell these cars with Weber carbs new and they started and ran nicely. I went back to the initial settings for the Weber’s including low speed mixture and ultimately fuel pressure at 3 psi. I installed an MSD 6A ignition. It then started, idled and took throttle nicely. That MSD does pack quite a wallop when I tried to put a loose plug wire back on even using insulated pliers.

Charlie

I picked up the MSD box and their coil a couple weeks ago, but then a hip replacement followed by internal bleeding has slowed me down a bit. I also was trying to run her with a (good) coil and points. A Pertronix is also on the way.

Where did you mount the MSD box?


Thank you all

I bolted the MSB box to the firewall. There is a little more room in an early 911 engine compartment than a 914-6. I might think about putting it in the rear trunk and running the wires thru one of the plastic domes.

Charlie

[930cabman]

Running the compression test WILL verify cam timing!
Sort of...

The thing that most effects compression test readings is intake valve closure.

If you have a cam timing screw up on one side, you WILL have similar compression readings per bank but the readings between the two banks will differ.

Driver side all read 190 and passenger side all read 145 you have a cam timing issue.

It's also the reason I mentioned checking valve adjustment before tear down.

The valves adjusted incorrectly will vary compression readings although not nearly as much as the cam timing being out.

Have you done a compression test yet?

I just love the offset cam timing holes like the 911 has. You can alter your cam timing without having to buy special gears or strange "offset" bushings.
That set up is "completely adjustable" cam timing from the factory!
It requires that the technician fully understands what he's doing but is "THE WAY" in my book for adjustable cam timing. They all aught to be like that!

No compression test yet, funny, my doctor prior to hip replacement a week and a half ago was adamant " do not work on cars for at least 4 weeks" and she had no idea I was a 914 nut

I am hoping next week to get back into the car shop

[930cabman]

I had the same issue with the 2.7 that I put together for my 68 911. I did all of the compression, spark, fuel verification. There were two issues. I was trying to run the 2.7 without a CDI box and fuel pressure was too high. I thought, they used to sell these cars with Weber carbs new and they started and ran nicely. I went back to the initial settings for the Weber’s including low speed mixture and ultimately fuel pressure at 3 psi. I installed an MSD 6A ignition. It then started, idled and took throttle nicely. That MSD does pack quite a wallop when I tried to put a loose plug wire back on even using insulated pliers.

Charlie

I picked up the MSD box and their coil a couple weeks ago, but then a hip replacement followed by internal bleeding has slowed me down a bit. I also was trying to run her with a (good) coil and points. A Pertronix is also on the way.

Where did you mount the MSD box?


Thank you all

I bolted the MSB box to the firewall. There is a little more room in an early 911 engine compartment than a 914-6. I might think about putting it in the rear trunk and running the wires thru one of the plastic domes.

Charlie

I am thinking inside the trunk, as being away from the battery. Hopefully the cables are long enough.

[Root_Werks]

Would certainly do a simple compression test, just to make sure those numbers are good enough to start the engine.

Would agree with most, probably something simple, timing too far or ignition switch cutting power after you let off the start position.

Would really hope the cams are not 180 out. (IMG:style_emoticons/default/sad.gif)

My engine builder has probably built hundreds of 911 engines, I suspect the fault does not lie with the engine internals.

dumb question: how/why would the power to the coil not be energized after releasing the ignition switch?

Prior to the /6 conversion, she was a running /4. Nothing was changed in the main wiring harness

Could be a bad ignition switch, it happens. Easy to test. Just ensure the terminal that powers the coil/CDI stays alive in Run and Start positions.

Fingers crossed it's still something simple. Others have already said, if compression comes back really low, likely not a good sign. Could try to squirt some LR2 (for you aviation folks) down each plug hole and try again. If numbers are still really low, likely cam timing or very ill adjusted valve lash.

[flyer86d]

Would certainly do a simple compression test, just to make sure those numbers are good enough to start the engine.

Would agree with most, probably something simple, timing too far or ignition switch cutting power after you let off the start position.

Would really hope the cams are not 180 out. (IMG:style_emoticons/default/sad.gif)

My engine builder has probably built hundreds of 911 engines, I suspect the fault does not lie with the engine internals.

dumb question: how/why would the power to the coil not be energized after releasing the ignition switch?

Prior to the /6 conversion, she was a running /4. Nothing was changed in the main wiring harness

Could be a bad ignition switch, it happens. Easy to test. Just ensure the terminal that powers the coil/CDI stays alive in Run and Start positions.

Fingers crossed it's still something simple. Others have already said, if compression comes back really low, likely not a good sign. Could try to squirt some LR2 (for you aviation folks) down each plug hole and try again. If numbers are still really low, likely cam timing or very ill adjusted valve lash.

I’ve seen ignition switches fail as you described. It will try to run while cranking the starter and quit as soon as the key is released.

Charlie

[gereed75]

I had the exact same symptoms.

Changed the ignition switch. Much better. Maybe the contacts get oxidized or fried in the run position because they are in the closed position for so long while running??

Much worse on cold days for some inexplicable reason.

[930cabman]

I had the exact same symptoms.

Changed the ignition switch. Much better. Maybe the contacts get oxidized or fried in the run position because they are in the closed position for so long while running??

Much worse on cold days for some inexplicable reason.

After 50 years, this stuff does wear out. This a simple test procedure, but maybe not so simple to change it out.

[930cabman]

Checked power at the coil + terminal, solid 12volts. Wants to start (almost) when cranking, but nothing when I release the key to the run position. Almost feels like the ignition system is being fed with 6 volts.

Sure wishin I could get this project moving.

[Root_Werks]

Checked power at the coil + terminal, solid 12volts. Wants to start (almost) when cranking, but nothing when I release the key to the run position. Almost feels like the ignition system is being fed with 6 volts.

Sure wishin I could get this project moving.

I have long test wires so if I want to sit in the car while cranking, can watch a volt meter. Make a couple of 10ft wires with little clips, test yourself. Cheap and easy. Will eliminate or confirm at least one possible issue.

I still think (a rather dangerous pastime of mine) your ignition switch is dropping or cutting voltage when returning from start to run positions. Could totally be something else, but symptoms sure fit the potential cause.

[930cabman]

I have noticed a rather large (more than I am used to) spark when I connect the battery. I have removed all of the fuses, but it's possible there is a short somewhere. Finding it can be a bit tricky.

Good idea to check the voltage when cranking

[Geezer914]

Any possibility of a vacuum leak?

[930cabman]

Any possibility of a vacuum leak?

Thanks, but it doesn't appear so.

I attempted to connect an ammeter in series with the battery+ terminal and the + cable. I blew the fuse in my VOM, so I am suspecting there is too much of a current draw somewhere. Not sure how to track it down.

[Superhawk996]

Any possibility of a vacuum leak?

Thanks, but it doesn't appear so.

I attempted to connect an ammeter in series with the battery+ terminal and the + cable. I blew the fuse in my VOM, so I am suspecting there is too much of a current draw somewhere. Not sure how to track it down.

Ammeter is good for 10 amps. If you tried cranking that draws about 75-100A.

If you blew a 10A fuse with just ignition on, then you definitely have a VERY large current draw somewhere. Coil / CDI box should only be 4-6A draw. Lights or other large current drains turned on at ignition on could take you well over 10A fuse.

You either need a shunt resistor or a DC capable current clamp if you want to measure more than 10A directly.

Have you confirmed the basics yet?

PS - why are you measuring current? To confirm the coil while cranking you only need to monitor voltage at the coil while cranking.

[930cabman]

Any possibility of a vacuum leak?

Thanks, but it doesn't appear so.

I attempted to connect an ammeter in series with the battery+ terminal and the + cable. I blew the fuse in my VOM, so I am suspecting there is too much of a current draw somewhere. Not sure how to track it down.

Ammeter is good for 10 amps. If you tried cranking that draws about 75-100A.

If you blew a 10A fuse with just ignition on, then you definitely have a VERY large current draw somewhere. Coil / CDI box should only be 4-6A draw. Lights or other large current drains turned on at ignition on could take you well over 10A fuse.

You either need a shunt resistor or a DC capable current clamp if you want to measure more than 10A directly.

Have you confirmed the basics yet?

PS - why are you measuring current? To confirm the coil while cranking you only need to monitor voltage at the coil while cranking.

Basics, yes. Fuel, compression, spark timing ok with spark.

With everything off, just connecting the battery I get a larger spark than I would like. I am suspecting a large current draw, earlier I disconnected the alternator with no change. Pver the past several months I did some metal work, hell hole and other misc metal repairs in the engine bay as well as adding a /6 mount. Hoping I did not damage any wiring within the main harness.

Thanks

[IronHillRestorations]

I’m going to guess the distributor timing is incorrect or 180* out. Very easy to do. Pull the valve covers to confirm.

If you have a early 911/914-6 style flywheel the marks on the rim of the flywheel won’t line up with the marks on the crank pulley on the 2.7, you have to remark Z1, 120*, 240* and the timing mark. The crank throws on a 2.4 and 2.7 are different.

[thomasotten]

Distributor firing order.

[930cabman]

Checking ohms across the + battery cable (when disconnected) and the negative cable should be 0 ohms. Correct or incorrect?

This is confirmed with my well running 2056, 0 ohms

Moving to my /6 conversion, not so. Checking across the + battery cable (when disconnected) and the negative battery I am getting 170 ohms

Checking across one pair of red cables ( normally connected to the + battery cable) and the negative cable I am getting a reading of approx 400 ohms, but quickly goes to much higher reading.

Checking across the MSD heavy red cable and the battery negative cable I am reading 12K ohms

Currently putting a full charge in the battery, will try for actual voltage when cranking. I suspect there is a short or more somewhere.

[Superhawk996]

Checking ohms across the + battery cable (when disconnected) and the negative cable should be 0 ohms. Correct or incorrect?

This is confirmed with my well running 2056, 0 ohms

Moving to my /6 conversion, not so. Checking across the + battery cable (when disconnected) and the negative battery I am getting 170 ohms

Checking across one pair of red cables ( normally connected to the + battery cable) and the negative cable I am getting a reading of approx 400 ohms, but quickly goes to much higher reading.

Checking across the MSD heavy red cable and the battery negative cable I am reading 12K ohms

Currently putting a full charge in the battery, will try for actual voltage when cranking. I suspect there is a short or more somewhere.

Not sure how to respond since it’s not clear to me what you’re measuring and under what conditions.

Short answer; with ignition off and both the battery + and battery negative (-) disconnected from the battery, you should see an open circuit (infinite) ohms assuming you have no parasitic loads like radio memory, the 914 center console clock, etc.

Not sure how you could possibly be measuring zero ohms on the /4. Zero ohms would represent a short circuit and then when you connect the battery, the cables would get hot, melt insulation, and glow red hot.

So you are not using the meter properly, or I’m not understanding what you’re doing.

[930cabman]

Checking ohms across the + battery cable (when disconnected) and the negative cable should be 0 ohms. Correct or incorrect?

This is confirmed with my well running 2056, 0 ohms

Moving to my /6 conversion, not so. Checking across the + battery cable (when disconnected) and the negative battery I am getting 170 ohms

Checking across one pair of red cables ( normally connected to the + battery cable) and the negative cable I am getting a reading of approx 400 ohms, but quickly goes to much higher reading.

Checking across the MSD heavy red cable and the battery negative cable I am reading 12K ohms

Currently putting a full charge in the battery, will try for actual voltage when cranking. I suspect there is a short or more somewhere.

Not sure how to respond since it’s not clear to me what you’re measuring and under what conditions.

Short answer; with ignition off and both the battery + and battery negative (-) disconnected from the battery, you should see an open circuit (infinite) ohms assuming you have no parasitic loads like radio memory, the 914 center console clock, etc.

Not sure how you could possibly be measuring zero ohms on the /4. Zero ohms would represent a short circuit and then when you connect the battery, the cables would get hot, melt insulation, and glow red hot.

So you are not using the meter properly, or I’m not understanding what you’re doing.

My mistake, infinate ohms on my 2056.

/6 conversion, quite different