Now I am stumped...

This is what happend:

Drove to hardware store, pulled in driveway, shut her off.

Forgot something, as usual, went to go start... will not start.

Checked spark- Have spark

Checked fuel- Have fuel

This was when it was really cold outside, so I shoved her up by the garage until spring.

Some reading on this site lead me to think that the timing could have jumped a tooth.

It was backfiring thru the carb when I was trying to start her before I parked the poor girl.

Checked Timing- Seems to be good

Checked timing by pulling #1 spark plug and rotating until at TDC. Rotor points at 1.

Then I pulled the front off the motor to inspect the timing set. Timing set is in good condition, and is a double roller!

But now I am stumped...

What else can I check?

What else could it be??

~J

I believe that when an engine is backfireing through the carb, and there is a loss of power and a reference is made to jumping a tooth regarding timing, that reference is valve timing, not electrical timing.

WHen you pulled the front cover did you check to make sure that he index marks lined up with the engine at TDC? There should be some kind of marking on the camshaft gear, and it should line up with another point in the housing, or a marking on another gear. This is to insure that your valves open and close properly in time with the compression and exhaust strokes.

The other timing is electrical. and that timing needs to be checked with a timing light. Opening the distributor cap and making sure that it is pointing at the correct cylinder is a great start, but it is very easy to be off 10 degrees or more like that. You may be able to crank the engine fast enough to set the timing without it running. BTW is your distributor loose? Could it have turned and changed spark timing?

I'd giver her a tuneup. Cap, points, rotor and condensor. Set the points with a feeler guage, and then check your work with a dwell meter. Then check the timing.

One thing that is often neglected when giving a tuneup is the backing plate inside the distributor that the points rest on. That often gets dirty and has an accumulation of evaporated oil film on it. That needs to be clean. Otherwise it will hold moisture, which is something you do not want on the inside of your cap.

Thanks for the insight...

I will check things out better tomarrow. I have to be at work in 5 hours, and I have yet to sleep!!

What is the gap supposed to be??

I am new to points... I have been working on computerized engines most my life...

~J

Jimmy Neutron said:

What is the gap supposed to be??I am new to points... I have been working on computerized engines most my life...

~J

Click to expand...

Jimmy,

I am sorry that I could not have been more specific and helpful.

1. I don't know what the gap should be. (I haven't gapped points since ~1980) You *may* find a label under the hood that will give you point and plug gap specs .. haha yea... right.

2. Please put info about your truck and engine in your signature file so that when possible specific advice can be given for your engine (go to my controls.. signature)

3. Valve timeing markings can be somewhat obscure. A chilton or Haynes manual for your engine would be helpful. Point gap and spark gap would be inter also.

So with the qualifications of the fact that therre is a LOT I do not know, I can share this thought with you.

When you set your points, clean the distributor cam (what the points rides on) I have seen them get gungky with caked on oil deposits, THEN apply a very thin coating of vaseline to it. SO thin that you put it on and wipe it off it is ok for a little bit of it to accumulate in front of the portion of the points that rides on the cam.

To set your points, you have to tap the starter with the points in, until the portion of the points that rides on the cam is at the tippy top of one of the cam points.

There were marks on both the cam shaft sprocket and the crank shaft sprocket... they point at eachother and laugh at me for all the work to get to see them. Rotten things! /emoticons/[email protected] 2x" width="20" height="20" />

Well, I guess I did find out two things during this inspection.

One being that I have a decent timing set that is in good condition, two being that my harmonic balancer is cracked...

I guess that last one may seem bad now, but its better that I find out this way rather than it failing and taking the motor out with it...

I will get that replaced and put everything back together and start tinkering with the distributor....

My sig is complete, thanks for the suggestion!

The cap, rotor, points, and condenser were brand new three weeks before the problem started...

Considering that your engine is a '71 and IF the distributor was never changed, then once you get her started, you may want to take a look that the vacuum advance works, when you work the throttle, and you would want to check to make sure that the centrifugal advance works when you run the RPMS up a bit. IF the springs are weak from age, I don't know if it would be possible for them to allow the timing to go too far advanced for the RPM. IF you get it within specs, and have pinging at higher RPMs, that *might* be the case.

Good luck, cause I am out of suggestions.

joe

B Joe is right on........

The cap, rotor, points, and condenser were brand new three weeks before the problem started...

I've seen this B/4 where the new stuff just won't work...! (or won't work for very long.)

(Good quality is important here)

Plugs .030 dwell 27deg. points .021

I've seen these motors run with everything set wrong..just not as strong.

Timing, or poss. a stuck valve (or valves) causes pop-up thru the carb.

On some... I've blocked off the vac. adv. due to the s--t gas these days.....(to prevent pinging)

HTH

B

Bully Bob said:

Timing, or poss. a stuck valve (or valves) causes pop-up thru the carb.

Click to expand...

Hey.. good thinking Bully Bob!

A compression test should be able to nail that down, no?

And there is a trick to using a teaspoon of oil to differenciate between rings and valves. Now... if someone could remind me how it is done /emoticons/[email protected] 2x" width="20" height="20" />

Add oil = compression goes up = ring trouble. /emoticons/[email protected] 2x" width="20" height="20" />

I will keep you fellas updated as to what I am doing and what actually changed anything...

Right now I am waiting for parts... I ordered a distrbutor, the old one was pretty sloppy.

I am keeping the current timing chain, even though there is some slop in the chain.

(not enough to hit the timing cover) I was able to braze and sleeve the harmoic for now,

I will replace that as soon as I can... (no worries, it is the exact same weight and the exact

same balance)

What I have done:

Checked the cam to make sure it did not break

Checked the timing set to make sure it did not jump

Checked the plugs for signs of crank/rod damage

Bully Bob, Thanks for the Plugs .030 dwell 27deg. points .021 info!!

What I am doing:

Changing the distributor (looks original), keeping the cap/rotor/points/condesor

Putting the timing cover ect back together

Testing timing with a timing light

At this point, if she STILL don't fire, the cap/rotor/points/condesor gets ousted!!

I wish I had the dough for a compression tester... I do have a vac tester, but no com tester...

I can almost gaurentee that she needs to be straightend up/bored over...

Thanks for all the help, fellas!!

I am being sent away on buisness until thursday...

I will resume then!!

~J

J.

There are some cheaper comp. testers out there..Harbor Frt. for one.

And..., throw a pint/Qt. of Marvil Mystery Oil in the crankcase (when it runs)...that can loosen up stuck rings, etc.

I forgot to add that I planned on running a can of Seafoam thru the gas tank when I get her running...

or should I stick with the quart of Marvil's?

Seafoam did wonders for the Interceptor... better throttle response, smoother idle...

I would like to say better milage, but the odometer broke!

Found a $15 Compression tester at HF... may be picking that up soon!!

"....I planned on running a can of Seafoam thru the gas tank.."

I always suggest..."no cleaners in an older vehicle fuel system....unless it's been cleaned &/or replaced." (recently)

These "cleaners" can lift...& suspend, crud....only to create more problems down-stream.

Some Marvil in the tank is OK but great added to even old oil in the crankcase. It will free up sticky rings & valves.

Assuming there's no real damage.

I run "Castrol" 50/50 synthetic blend 10W40 and really noticed a diff. Don't need any additive with it..!

You can rent a good compression tester for a few bucks.

I have not seen anywhere you checked point gap or dwell. I would recomend that first. Messed up point gap will cause the problems listed and is very fast and easy to fix. Make sure you check to make sure the points are not fried prior to gapping them.

Sounds like you have a good working plan of action.

You mentioned atht at one point you may do this... <snip>

At this point, if she STILL don't fire, the cap/rotor/points/condesor gets ousted!!

<Snip>

Of those parts, considering that they are only three weeks old, I would only consider changing the condensor. It is really unlikly IMO that the other components would be bad.

I would use the money that would go to the other parts, and put it towards the purchase of a compression tester. OTOH... you may ask around, maybe a friend or neighbor has one you may borrow.

Sorry it has taken me so long to respond...

I ordered the distributor last week at a place where I get somewhat of a discount, they had to order it. Then it did not come in on the day they said it would so I called... they never ordered it! I called around to their competitors... made them go there and get it and sell it to me at the discounted price.

This is what I have done:

The new distributor came with points and a condenser, so I used them.

I set the gap to .021.

I checked the gap to .030 on the plugs and installed them.

I ran the spark plug wires in accordance with the 1-5-4-2-6-3-7-8 firing order.

I installed the new distributor, making sure it was on #1 for the distributor cap.

I cleaned and painted all the removed parts.

I RTV

BroncoJoe19 said:

Yahoo... you're almost there! /emoticons/[email protected] 2x" width="20" height="20" />
I don't know what would cause the coil to get piping hot, but I recalled Bebop man had an issue with his coils buring out.

THis was his solution:

After the events of last weekend (not starting, coils burning out), I took it into a local shop, and they had it for a week. They also toasted one of their coils, then started tearing stuff apart. They found that there was a couple wires that had melted and were rubbing up against the engine block. Replaced them, and everything seemed to work ok.

Happy hunting.

joe

Click to expand...

Sorry that I have no reference to help out here, but trying to think back. IF I recall properly, one of the two little wires to the coil is 12V from the battery, (ignition switch) and the other goes under the cap to the points and condensor. I would look closely at that wire, especially as it goes through the distributor, perhaps there is a little short there.

My guesses are:

That little wire

the condensor

wait... where that condensor and the coil wire connect to the points, isn't there a little insulator to keep them from grounding out to the base plate of the distributor? I know that it is new, but I have to ask are they grounding when they shouldn't be? Seems to me that if they were grounding the condensor wouldn't be able to store engouh charge for a spark to jump a gap, but I am just reaching here.

finally... is it poossible that you have two bad coils?

It's always a possibility to have two bad coils, but unlikely...

I am starting to remember that the old coil was getting hot, so I replaced it with a MSD coil.

BUT I also remembered last night that there was a rectangular resistor on the firewall that burnt up. I no longer see the resistor- but I see two wires temporarily twisted together. Any idea what that resistor is for?? Its about 2