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F350 losing power..... Help!

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86-350-460-dually

Re: F350 losing power..... Help!

Grumpin,

The clutch was replaced two or three weeks ago.

ArdWrknTrk,

Altitude is a factor. I live at 6k ft currently, and those passes were around 7-7.5k ft.

As for the EGR plate and gaskets, I honestly don't know if they are free and clear of the venturi's. I will pull the carb off today and look at them, because I just used what was on it before, assuming it had to be what would work best and put the new carb on top. I believe the old carb was the stock one. Motorcraft Holly.

Adam

1986 F-350, Dually 4WD, C/C with the 460/7.5L

ArdWrknTrk

Re: F350 losing power..... Help!

Administrator

Adam,
What caused you to swap carbs?

Check fuel delivery before you go to the trouble of pulling the carb, but I know it was an issue when I went from a Holley to my 650 AVS.

I used a scribe but you could just use a Sharpie marker and the Edelbrock's proper base gasket to match the ports.

Your gearing is going to cause your truck to have shorter legs than mine and a stock cam will run out of steam on top, but you should be able to easily pull 14k at 3,000 rpm with your rig.
If looking for more power on the cheap consider a straight up timing chain set.
BTW, how many miles are on the engine?

, Jim

Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake.
Too much other stuff to mention.

86-350-460-dually

Re: F350 losing power..... Help!

To answer your questions:

The carb did not have a choke on it when I bought it in December. It was a royal pain to start cold. Haha.

....as for the miles on it........ Well.... Not a stinking clue. Haha. I bought it and it says 6,000 miles. I have no clue how many times it has rolled over. Are you thinking of doing a compression test?

I do have access to a free 460 motor out of a motorhome that's been sitting for several years with only 48k original miles. The possibility of doing a motor swap has crossed my mind, but I'm a little pressed on time.

Adam

1986 F-350, Dually 4WD, C/C with the 460/7.5L

ArdWrknTrk

Re: F350 losing power..... Help!

Administrator

Stock timing chain with nylon gear is good for only 75,000 in my experience but if you have no trouble with the carb spitting back then I don't see that as the issue.

But wear will retard the cam even more than the stock eight crank degrees, and will cause a loss of power.
Consider dropping $50 on a Cloyes steel roller set if you ever need to replace the water pump.
At least the AIR pumps are out of your way already.

Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake.
Too much other stuff to mention.

86-350-460-dually

Re: F350 losing power..... Help!

That's good to know. What about timing? I set it to 11° without the vacuum advance hooked up to the distributor. I bought the truck and it was at 13°-14°. Any thoughts on that?

Adam

1986 F-350, Dually 4WD, C/C with the 460/7.5L

ArdWrknTrk

Re: F350 losing power..... Help!

Administrator

In reply to this post by ArdWrknTrk

So, I was really thinking of the timing chain when I asked about mileage.
This is different than ignition timing.
11degrees sounds like a good place to start.

My truck made it to 280,000 with regular maintenance before it spun a rod bearing on a bitter cold morning.
Another 150k in the past 11 years on a reman motor, and I wouldn't expect a dedicated tow rig to see nearly that.

But if it's 106,000 on a stock nylon gear you are past due for replacement.

Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake.
Too much other stuff to mention.

ArdWrknTrk

Re: F350 losing power..... Help!

Administrator

In reply to this post by 86-350-460-dually

Was the truck having an issue with spark knock at 14°?

If you want to know how to optimize ignition timing go to the Jeg's site and look up the Crane adjustable vacuum advance unit for '70's Ford & Mercury. Under documentation they have a PDF of the instructions.
These are detailed and have to be followed in proper order.

Bill (85 Lebaront2) owned a tune-up shop and can detail what to do.
But if it was working before the swap I wouldn't mess with it now.
You have too much else to do in the coming weeks.

Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake.
Too much other stuff to mention.

86-350-460-dually

Re: F350 losing power..... Help!

Ok. That's really good to know. Thanks. First things first, check fuel pressure at higher speeds.

Adam

1986 F-350, Dually 4WD, C/C with the 460/7.5L

ArdWrknTrk

Re: F350 losing power..... Help!

Administrator

It's an electric pump.
It's either off or on.

This is why Bill said to check volume not pressure.
And why I said to check after the screen of the vapor separator.

You can jumper the fuel pump relay to test while you have the hood open looking at the fuel flow.

Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake.
Too much other stuff to mention.

FuzzFace2

Re: F350 losing power..... Help!

I was thinking plugged cat till I saw the truck and would say it does not have a cat.
Now if the fuel volume checks out I would take a rubber or dead blow hammer to the muffler and give it a few hits.

I am thinking 1 of the baffles broke loose inside and is blocking the flow.
I have seen this happen and when the muffler is hit you will hear it rattle as the baffle moves around.
Or could if easy drop the muffler out of the system and take it for a spin.
Dave ----

Dave G.
81 F100 flare side 300 six / AA OD / NP435 / 2.75 gear
http://cars.grantskingdom1.com/index.php/1980-Ford-F100?page=1
81 F100 style side 300 six/SROD parts truck -RIP
http://cars.grantskingdom1.com/index.php/1981-Ford-F100

86-350-460-dually

Re: F350 losing power..... Help!

In reply to this post by 86-350-460-dually

Thanks everyone for the help. It actually did help out a ton. So I was able to swap out the rear tanks fuel pump assembly successfully today. I did discover another issue, as with most things on this truck haha.

My fuel tank selector dew-hickey is not switching tanks properly and is getting stuck between the switches.

So my question to you is, what in the world is the difference between these selector valves on O'Reilly's website? They have about 6 to choose from, from $45-$650 for the unit. I read the descriptions and they sound the exact same to me. Any suggestions?

Adam

1986 F-350, Dually 4WD, C/C with the 460/7.5L

85lebaront2

Re: F350 losing power..... Help!

Administrator

The selector valve you have is peculiar to the 1986 models if I remember correctly. It has the 6 ports, 3 supply and 3 return, and is motor operated, but also includes the switch for the fuel gauge senders: http://www.garysgaragemahal.com/fuel-tank-selector--gauges1.html Unless one of the ones you are looking at is an exact replacement for the original see if any of the ones you are looking at gives a Ford PN, it should be an E with a number, probably will be a 4 (possibly) 5 or 6 indicating the year of release. Gary's part number list shows it as E5TZ-9189-B, there is also an E3TZ-9189-C, but it is listed as 1983-1985 models, so the 1986 is unique to 1986 models. Unfortunately the one I pulled off Darth when I went to EFI is long gone to someone on FTE.

Bill AKA "LOBO" Profile

"Getting old is inevitable, growing up is optional" Darth Vader 1986 F350 460 converted to MAF/SEFI, E4OD 12X3 1/2 rear brakes, traction loc 3:55 gear, 160 amp 3G alternator Wife's 2011 Flex Limited Daily Driver 2009 Flex Limited with factory tow package Project car 1986 Chrysler LeBaron convertible 2.2L Turbo II, modified A413

ArdWrknTrk

Re: F350 losing power..... Help!

Administrator

Bill,

Since you have (had) an '86 460 with in-tank pumps can you tell what is unique about this year?
I've heard a lot of 460 & diesel guys retrofitting the unobtainable Ford switch valve with the Pollak 42-302 six port kit.

Maybe Jonathan knows something about it too?

Yes, you have to wire the new pigtail plug and eliminate the Ford nylon hose end clips.
This motor driven valve does switch senders and has 3/8 supply with 5/16 return ports.

My understanding is it's widely available in the aftermarket.

Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake.
Too much other stuff to mention.

ArdWrknTrk

Re: F350 losing power..... Help!

Administrator

This post was updated on .

FWIW, here's the variety of suppliers the Pollak selector valve is sold under.
(Edit) Be sure to get a *kit* that includes the plug.

Maybe O'Reillys stocks one of them?

42-302 42-302P 6 Port Fuel Tank Selector Valve Kit Harness - Gas Diesel

ACDELCO GM ORIGINAL EQUIPMENT 14029228
ACDELCO GM ORIGINAL EQUIPMENT CANADA 14029228
AIRTEX AUTOMOTIVE DIVISION 8F1312
BWD AUTOMOTIVE FSV3
CARQUEST 541701
CARQUEST/STANDARD MOTOR PRODS. 541701
CARQUEST/STANDARD MOTOR PRODS. FV5
CARQUEST/WELLS 541701
ECHLIN 22198
FEDERATED IGNITION FSV3
GP SORENSEN FSV2
KEMPARTS FTV2
NAPA 22198
NAPA 32198
NAPA/ECHLIN FUEL SYSTEM-CRB 22198
NAPA/MILEAGE PLUS FUEL-MPF 32198
NIEHOFF UN52
POLLAK 42149
POLLAK 42203
SIERRA MARINE FSV2
WELLS 541701
WELLS FSV2

Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake.
Too much other stuff to mention.

85lebaront2

Re: F350 losing power..... Help!

Administrator

In reply to this post by ArdWrknTrk

Jim, the changes were in the power source for the selector valve, through 1985 it was fed with 12V from one of the fuses, starting in 1986 it is fed from the pump feed circuit, meaning battery feed through the small fusible link when cranking and through the pump feed once running. This means the valve will not change position with the dash switch unless you are cranking the engine or the truck is running.

Real fun if one tank runs out and the engine cuts off, because at this point if you don't still have some oil pressure, it will not switch until you turn the key to "start".

Bill AKA "LOBO" Profile

1986F150Six

Re: F350 losing power..... Help!

Administrator

In reply to this post by 85lebaront2

85lebaront2 wrote

The selector valve you have is peculiar to the 1986 models if I remember correctly. It has the 6 ports, 3 supply and 3 return, and is motor operated, but also includes the switch for the fuel gauge senders: http://www.garysgaragemahal.com/fuel-tank-selector--gauges1.html Unless one of the ones you are looking at is an exact replacement for the original see if any of the ones you are looking at gives a Ford PN, it should be an E with a number, probably will be a 4 (possibly) 5 or 6 indicating the year of release. Gary's part number list shows it as E5TZ-9189-B, there is also an E3TZ-9189-C, but it is listed as 1983-1985 models, so the 1986 is unique to 1986 models. Unfortunately the one I pulled off Darth when I went to EFI is long gone to someone on FTE.

https://www.ebay.com/sch/i.html?_from=R40&_nkw=E5TZ-9189-B&_sacat=6030&_sop=15

85lebaront2

Re: F350 losing power..... Help!

Administrator

They're proud of those aren't they? Glad I no longer have one on Darth.

Bill AKA "LOBO" Profile

ArdWrknTrk

Re: F350 losing power..... Help!

Administrator

The aftermarket alternative is about $70 with the pigtail plug.
You do have to modify the stock harness and lines.

OEM may have lasted 33 years.
I know I've never changed mine.
If I did I'd save the $250 to put in the tanks.

Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake.
Too much other stuff to mention.