Vacuum leak?

[majestic]

So my son has created his first breakdown in the SVO. He said that driving it home the boost gauge will still function but there is not boost/power. I tried to start it and it idles very rough and dies. I assumed a ruptured intercooler hose but they both look fine after taking them off. I can't find any issues with the vam or the other bcs hoses. Any ideas?

[brsvo]

Would help to know how it was running before and what happened at the point of failure. Check for melted plug wires, fuel pressure and ignition timing to start.

[majestic]

Would help to know how it was running before and what happened at the point of failure. Check for melted plug wires, fuel pressure and ignition timing to start.

He said it was running fine but felt a little sluggish. I assumed due to the heat as it's been around 100 here lately. He pulled into the driveway and it was idling fine. I'll keep looking. I order some new ic hoses just in case.

[MikeFleming]

Get a can of Starting Fluid (usually 90%+ ether) and lightly spray it around the suspected leak areas when held at a high idle.

Wait ten seconds between spraying different areas. Specifically avoid the intake nozzle/filter area.

If there are any leaks there will be an almost immediate change in RPM and, usually, rabid pinging for the duration of the spray.

Use only in a well-ventilated area. Breathing that stuff will make you sick real quick.

Repair/replace as needed.

[majestic]

I'm leaning towards a defective TFI module. After putting the intercooler back on and tightening everything down, we were finally able to get it to idle after about 10 attempts. It is making boost while in neutral, which seems weird. We drove it down the road and it boosts way down in the rev range and runs very hot. Does this sound like a bad TFI, or maybe a bad fuel pump?

(Oh, and my son wants to make sure I point out that he didn't break the car)

[DaveS]

I left the SPOUT connector off once and it ran like you describe above. What does the timing look like? Does it change when the SPOUT is connected?

[majestic]

I left the SPOUT connector off once and it ran like you describe above. What does the timing look like? Does it change when the SPOUT is connected?
I haven't touched the "pill", nor have I checked timing. I went ahead and ordered a new TFI and a 255 Walbro just to be safe. We'll get those installed in a couple of weeks and see how things go. I need to research remote mounting the TFI like I did many moons ago. That really seemed to help with the TFI issues. I have the new IC hoses with t-band clamps on the way. Will probably order a PIMP in the next couple of months to get rid of the VAM and start towards exhaust and intercooler after that.

[MikeFleming]

Ignition timing is severely retarded. Check:
- cam belt/timing
- dist gear
- timing
- SPOUT connector/pill

[majestic]

Ignition timing is severely retarded. Check:
- cam belt/timing
- dist gear
- timing
- SPOUT connector/pill

Here is the weird thing. When attempting to start, it will stutter and I have the throttle wide open to keep it running. After about 45 seconds of WOT, it will suddenly rev up and idle normally. Does this sound like a fuel pump? I'll have to rummage through the garage and see if I can find my timing light. It's been so long since I worked on one of these that I'm not sure I even remember how.

[MikeFleming]

One more item I thought about late last PM:

- plugged/severely restricted exhaust.

BTW - stop running it until this issue is sorted. Those high EGTs will start destroying things quickly.

Fuel is easy enough ot test for - install fuel pressure gauge. One can also kinda get a feeling for exhaust restriction by watching a vacuum gauge while cranking with closed throttle. If it's not bouncing to at least 10" Hg, there is an issue.

Cam belt, cam and dist timing and dist/aux shaft gears are also fairly easy to test. Check cam timing and belt/tensioner condition and if OK, pull the dizzy and inspect the gear.

Repair, replace as needed.

[majestic]

One more item I thought about late last PM:

- plugged/severely restricted exhaust.

BTW - stop running it until this issue is sorted. Those high EGTs will start destroying things quickly.

Fuel is easy enough ot test for - install fuel pressure gauge. One can also kinda get a feeling for exhaust restriction by watching a vacuum gauge while cranking with closed throttle. If it's not bouncing to at least 10" Hg, there is an issue.

Cam belt, cam and dist timing and dist/aux shaft gears are also fairly easy to test. Check cam timing and belt/tensioner condition and if OK, pull the dizzy and inspect the gear.

Repair, replace as needed.

Yes, it's too hot to work on right now anyway.

I am re-amassing tools that I got rid of long ago. I just purchased a fuel pressure tester. I'm going to have to do some Google searching to remember how to check/set cam timing, etc. I'm still wondering what the deal with having to hold WOT for 30-45 seconds before it runs is, but if the temp comes down below 90 in the next couple of days, I'll start by checking the fuel pressure.

[Under Pressure]

I had the similar thing going on with mine til the car died. It was the distributor gear slipping til it didn't have enough teeth to work.

[majestic]

I'll add that to the list :( I wish I had someone around here that knew how to work on these cars. I've gotten somewhat lazy when it comes to in-depth mechanical stuff.

[majestic]

Here is the plan at the moment. Assuming the weather is cooler/rain-free on Friday, I'm going to progress in this order:

*replace TFI and attempt to start, if no...
*check fuel pressure at the rail, if not 40, replace pump, if 40...
*pull timing cover and check cam and other timing marks, if aligned...
*pull dizzy and check for wear, if bad, replace distributor, drop pan to remove shavings, change oil and filter and check timing, if that doesn't fix it...
*have it towed to the shop and let them deal with it :(

Suggestions?

[DaveS]

I always like to start with cheap and easy first. From your description, it sounds like an ignition timing thing to me. If it were me, I'd go in this order:
*pull dizzy and check for wear, if bad, replace distributor, drop pan to remove shavings, change oil and filter and check timing, if that doesn't fix it... (not easy if you have to pull the pan, but at least then you know you've found something).
*pull timing cover and check cam and other timing marks, if aligned...
*check fuel pressure at the rail, if not 40, replace pump, if 40...
*replace TFI and attempt to start, if no...
*have it towed to the shop and let them deal with it :(

I'm going through a dizzy gear issue on my '84 now. sigh. Reluctant to start it as I remember the rash of broken dizzy gears about 4 or 5 years ago. I'm measuring everything and checking to make sure it is within specs. We'll see how it goes.

So far, I'm pleased with my rebuilder; pricer than Cardone, but I believe better quality and much better customer service. I've spoke with him on the phone several times.
Dave

[majestic]

I always like to start with cheap and easy first. From your description, it sounds like an ignition timing thing to me. If it were me, I'd go in this order:
*pull dizzy and check for wear, if bad, replace distributor, drop pan to remove shavings, change oil and filter and check timing, if that doesn't fix it... (not easy if you have to pull the pan, but at least then you know you've found something).
*pull timing cover and check cam and other timing marks, if aligned...
*check fuel pressure at the rail, if not 40, replace pump, if 40...
*replace TFI and attempt to start, if no...
*have it towed to the shop and let them deal with it :(

I'm going through a dizzy gear issue on my '84 now. sigh. Reluctant to start it as I remember the rash of broken dizzy gears about 4 or 5 years ago. I'm measuring everything and checking to make sure it is within specs. We'll see how it goes.

So far, I'm pleased with my rebuilder; pricer than Cardone, but I believe better quality and much better customer service. I've spoke with him on the phone several times.
Dave

I'll give it a shot, Dave. I went ahead and ordered a remanufactured dizzy from Cardone just in case. I should have everything ready for Friday. I should just be able to mark the old one and put the new one in along that mark, right?

[majestic]

Wait....if memory serves, you can't really drop the pan without a major undertaking. Would just changing the oil and filter work if it turns out to be the distributor? (Depending on how chewed up the gears are, of course)

[8T6 SVO]

Wait....if memory serves, you can't really drop the pan without a major undertaking. Would just changing the oil and filter work if it turns out to be the distributor? (Depending on how chewed up the gears are, of course)

Risky if you rely on just changing oil/filter, I guess you could always get a magnetic oil drain plug to help with this course of action. I know the magnetic plugs won't be 100%, but I do remember my SVO having a large magnet stuck to the outside bottom of the oil pan (car came with this - old racing SVO) and might help for concerns such as yours.

[DaveS]

OK, having 24 hours to rethink this, here is what my approach would be:


Remove timing cover, check cam timing. Remove timing belt and see what effort it takes to rotate the Aux. shaft; see if dizzy rotor spins smoothly.
Replace TFI
Check fuel pressure
Replace PIP, in your situation…install rebuilt dizzy.

This will check for engine timing, dizzy gear, TFI, fuel pressure, bad PIP….with removing and replacing the dizzy as late as possible. I’ve always tried to leave the dizzy gear to aux gear untouched as they wear together. Both the aux shaft and the dizzy gear have the same number of teeth, so if you remove and restab the dizzy, you may alter which aux shaft tooth hits which dizzy gear tooth.
If I had a bad dizzy gear, I’d not only pull the oil pan but clean up what I could from the upper engine. I’d not be comfortable just changing the oil filter. Once the debris gets past the oil pump pickup screen, it will hit the oil pump before it hits the oil filter, not a risk I’m willing to take.
I’m cautiously installing a rebuilt dizzy in my ’84. Taking measurements, checking tolerances, and thinking a lot. I really don’t want to have to pull my oil pan to clean up dizzy teeth debris. Once I’m convinced I’m successful, I’ll post what I did. FYI, about 5 or 6 years ago, there was a huge number of dizzy gears disintegrating…Not sure what caused it, but I’m trying to make sure it doesn’t happen to me when I start my ’84 with the rebuilt dizzy.

[majestic]

It's at Ford. I did the easy stuff, to me, at least, and didn't find out what the problem was. Fuel pressure was fine and the new TFI didn't fix anything. There was an oil leak, which I knew about, that Ford says leaked onto the timing belt and caused/allowed it to jump a tooth or two. They are going to fix the oil leak, replace the timing belt and tensioner, install the new distributor (that I already had) and flush-out the engine. New oil and filter, of course. How does $1100 sound to you? :(

[DaveS]

Just my opinion....Sounds kind of pricey to me. Should be no more than a 3 or 4 hour job, the timing belt set is about $30, oil & filter another $30, the gasket set about $20. The engine flush must be pricey (I would be curious as to what constitutes an engine flush though)!
As many problems that were had with distributor gears failing a few years ago, if your distributor is OK, I'd leave it alone.
I'm in the process of replacing my dizzy and plan to post what I do once complete. To say I'm overthinking it would likely be an understatement. I don't want to have to clean out dizzy gear pieces from my engine.

[majestic]

Just my opinion....Sounds kind of pricey to me. Should be no more than a 3 or 4 hour job, the timing belt set is about $30, oil & filter another $30, the gasket set about $20. The engine flush must be pricey (I would be curious as to what constitutes an engine flush though)!
As many problems that were had with distributor gears failing a few years ago, if your distributor is OK, I'd leave it alone.
I'm in the process of replacing my dizzy and plan to post what I do once complete. To say I'm overthinking it would likely be an understatement. I don't want to have to clean out dizzy gear pieces from my engine.
Too late now :)

[majestic]

Just picked it up a couple of hours ago. Runs nice and smooth and no knocking. I went ahead and swapped out the IC hoses for the ones Stinger sells with the band clamps. I left the IC brackets off as the new hoses are pretty stout. Going to try and drive it easy for a couple of weeks to let everything mesh together.

[DaveS]

Good news, I just hope my current project (install rebuilt dizzy with new gear) goes this well.