List of known issues, first things to break?

[alexmak]

When reading this forum, I often see a discussion that goes like “ah, yes, that’s something expected to break”, or “I joined the club of X…”. One thing I remember is a windshield that cracks for many, so I am morally prepared for that already.

I discovered another thing today. When driving home at night I realized my brake lights are not working. Got home, half an hour of investigation later I discover it’s the brake lights switch that’s at fault. OK, I need a replacement, let me google the forum for it. And the first result I see is “Like many others... my brake light switch broke”. (I ended up buying a Standard Motor Products one, as the AC Delco one is not available on Amazon at the moment).

Anyway, this got me thinking — what else is there that is known to break? What is something many of you experienced that is common? I got so many useful suggestions from this forum with the stuff that I should use in the build to improve the process and the results, so now that I’m done, would be terrific for me (and for many others, I’m sure) to know what to expect :)

[NAZ]

The only thing you should expect to break is the rear tires as you smoke em down the street.

[J R Jones]

alex, Your signature looks solid. Used donor parts are a crap shoot.
The windshield thing appears to be pre-load from forcing the glass to fit the frame.
Other than that is is my observation that failures are fastener related. Assembly technique is everything.
jim

[j.miller]

I broke my wallet 3 times....JUS SAYIN !!! ...da Bat

[egchewy79]

If you have the vintage speed hut gauges, add the oil pressure sender to this list. They are very accommodating and will send you a new one pretty quickly, but it's always unnerving to see your oil pressure drop to 0. Currently on my 2nd sender and have it plugged directly into the block, but am prepared to make a remote sender bracket if necessary.

[Papa]

If you have the vintage speed hut gauges, add the oil pressure sender to this list. They are very accommodating and will send you a new one pretty quickly, but it's always unnerving to see your oil pressure drop to 0. Currently on my 2nd sender and have it plugged directly into the block, but am prepared to make a remote sender bracket if necessary.

Or you could just use one of these:

https://www.summitracing.com/parts/sum-220699?seid=srese1&gclid=Cj0KCQjwkIGKBhCxARIsAINMioJovppapOSbgxKfLDyf 6yerYLuU75xSjXFLENHl3AqMSjbiIXMzoWAaAv0YEALw_wcB

[Papa]

What I've replaced so far:

1. Gas cap
2. Gas fill tube seal
3. Ball joint boots

And my latest adventure, which is likely self-induced, I get to replace my water pump. My engine sat for several months before installing it and the coolant was filthy after the initial startup. I drained and re-filled, but really should have done a complete flush. I have everything sitting on a shelf to do it and kept putting it off. Now I'm paying for my procrastination. At least with the lift, I can access it pretty easilly from the bottom side.

[alexmak]

I broke my wallet 3 times....JUS SAYIN !!! ...da Bat

I'm three times over the initial (imagined) budget, so I know the pain very well :)

[alexmak]

If you have the vintage speed hut gauges, add the oil pressure sender to this list. They are very accommodating and will send you a new one pretty quickly, but it's always unnerving to see your oil pressure drop to 0. Currently on my 2nd sender and have it plugged directly into the block, but am prepared to make a remote sender bracket if necessary.

I don't have oil pressure gauge, although I'm thinking of adding one (if I decide to redo the dash). will consider this. Although I remember breaking coolant temperature sender when tightening it - apparently it's also a common thing

[alexmak]

What I've replaced so far:

1. Gas cap
2. Gas fill tube seal
3. Ball joint boots

And my latest adventure, which is likely self-induced, I get to replace my water pump. My engine sat for several months before installing it and the coolant was filthy after the initial startup. I drained and re-filled, but really should have done a complete flush. I have everything sitting on a shelf to do it and kept putting it off. Now I'm paying for my procrastination. At least with the lift, I can access it pretty easilly from the bottom side.

oh, right, I have the new set of ball joints boots ready for replacement. just waiting for a bad weather fall weekend. somewhat dreading the project of doing all of them.

[kgkeys]

For those with shorty headers/j-pipes, the F5 remote oil filter kit always leaks. The Ford Performance parts 90 degree adapter seems to be the most common replacement part.

-Kyle

[egchewy79]

Or you could just use one of these:

https://www.summitracing.com/parts/sum-220699?seid=srese1&gclid=Cj0KCQjwkIGKBhCxARIsAINMioJovppapOSbgxKfLDyf 6yerYLuU75xSjXFLENHl3AqMSjbiIXMzoWAaAv0YEALw_wcB

thought about it but heard that the vibration is actually worse at the end of the stem than directly in the block.
Not sure if it's the heat or vibration killing these senders, but the remote location would eliminate both issues.

[NAZ]

I've had these pressure transducer style sending units die from vibration before. So I mount them on the firewall and use a -3AN hose to connect to the engine.

153370

[OSU Cowboy]

Things that have failed on my MK3.1 with now 13K miles on it since Nov 2019 ...

1) Front brake calipers locked down on rotors at ~ 600 miles. Granted, I had the parts in the garage for 11 years during the build process ... likely had a heckuvalot to do with that. The back story on this event is that it happened the very first time I got my wife into the car. She was "quite emotional" around the idea that we were about to burn to the ground once I got stopped with smoke billowing from both front wheels. She was filled with confidence around my build talents as a result.

2) In tank fuel pump failed at ~ 5000 miles. Suspect the fuel pump hanger with 3/8" line out but only 1/4" line return (just in the hanger itself, I had the return line plumbed with 5/16") had a lot to do with that. I replaced the fuel pump and relay, and modified the new pump hanger for a 5/16" return line. I hope I some point I don't regret plumbing 5/16" return rather than 3/8".

3) Driver's side header forward pipe developed a hole / crack right at the flange where it bolts to the head. Happened around 7K miles. Thank goodness I have a nephew that is talented in these areas ... he tig welded it and got me back in business.

4) At various points, I've lost side pipe bolts / nuts. So check them periodically. I was advised to use brass nuts for removal purposes. Starting to think this is perhaps not the right thing to do. Jury still out on that one, although I've started to use nickel plated in place of any brass ones that I lose.

[OSU Cowboy]

Oh - how could I forget? This was the 2nd AAA flat bed ride home - first one being the fuel pump failure.

5) Hydraulic clutch slave failure at ~ 12K miles. Piston popped out. I think it was developing for some time, but I didn't know what to feel for in the clutch pedal action. No doubt, the original install and adjustment was incorrect. New slave installed and the adjustment is such that the clutch disengages well prior to the clutch pedal being actuated to it's full extent.

[FLPBFoot]

I had the fuel tank sending unit gasket start leaking after about 18 months and 2,500 miles. Replaced it with an o-ring rather than the square ring provided and been good ever since.

[AC Bill]

I can't say if the newer models have the same issues, as the older models did, when to comes to stuff failing. Some of the items that have routinely broken over the years, were not always the fault of the product itself. Poorly written, or incomplete instructions in the build manual, are responsible for some reoccurring issues. Builder error have also caused their fare share.
Some say the failure of the hundreds of cracked roadster windshields, is caused by incorrect installation. A few experts have found a method of installing them, claiming to solve the issue. My MK3.1 build manual certainly didn't detail any installation method that prevented cracking. I'm not sure if they amended them in future manuals, but they still seem to regularly crack, even on newer models. I blame Factory Five for A- Supplying a poor quality, Made in China product, and B-Poor/incomplete installation instructions.

Door latches breaking, have been an issue for some time now. There are preventive corrections, and a repair method discovered by builders, that can solve this. I'm not sure, but I suspect, that these latches may also be a cheaper, Chinese made product. There are 60 year old British cars still using the original door latches...

Some clutch cables had a habit of breaking. Fraying could occur, on the short metal tube welded to the inside back of the foot-box frame. This was most apparent with the builds using aftermarket clutch quadrants, and a donor pedal box.. During the quadrants arc, as it pulled back on the cable, it would raise the cable just enough to contact the upper edge of this tube. The constant rubbing under tension caused fatigue on the cable strands, which caused them to break one by one, until total failure occurred.
My research indicated that the aftermarket cables seemed to fail foremost, in comparison to the OEM Ford original Mustang 5.0 cables. Even the Ford Performance cables didn't have the stamina of the Fox body year cables. I don't know if you can even purchase the good ones any longer...

The supplied throttle cables also had their issues. Some of the problems with them often appeared to be the routing used for them by the builder, and/or exposure to heat. The cable housing would sometimes melt, and cause the cable to stick. Poor choice of cable routing, sometimes caused binding to occur. In a few cases, the barrel end would pull off the cable. This could often be attributed to not using a throttle pedal stop, or having the incorrect length on the cable to allow for WOT, without undue pressure applied to the cable.

[alexmak]

I had the fuel tank sending unit gasket start leaking after about 18 months and 2,500 miles. Replaced it with an o-ring rather than the square ring provided and been good ever since.

HA! I had it leaking after 500 miles! Had to drop down the tank to fix it.

[Al_C]

In my experience (just hit 2 years being legal), things don't break, they just get loose. Regular trips to a friend's lift are part of the maintenance routine now.

[alexmak]

In my experience (just hit 2 years being legal), things don't break, they just get loose. Regular trips to a friend's lift are part of the maintenance routine now.

I’ll make sure to tighten than brakes light switch as according to the torque specs! That will show it to it!

[toadster]

I haven't driven yet, but my wallet is sure broken! :)

[Railroad]

Sure would make a good "STICKY" That filler neck grommet is dangerous. Gas cap is a big NO, also. I have had no problems with the headlight and ignition switch, but have seen some reported quality issues. Got my fingers crossed on those two.

[nucjd19]

Sure would make a good "STICKY" That filler neck grommet is dangerous. Gas cap is a big NO, also. I have had no problems with the headlight and ignition switch, but have seen some reported quality issues. Got my fingers crossed on those two.

I worried and was very careful with that grommet throughout my build based on what everyone was saying and keeping an eye on it too.

[Railroad]

I worried and was very careful with that grommet throughout my build based on what everyone was saying and keeping an eye on it too.

Do us a favor and change the tank grommet out now. It is not how careful you are, it is the quality or lack of, in the material. Mine cracked and split. After reading so many reports of issues, I inspected mine. Sure enough, it was splitting.
It was not leaking, probably due to low fuel level, but was scary once in hand.

[RBachman]

Here's mine:
Ignition switch went bad
A brake caliper had a crack in the E-brake cable mount
Bad toggle switch
Bad connector on the fuel sending unit
Bad LED dimmer switch
Fan Belt frayed, (probably nicked it during assembly)
Leaking Power Steering Rack
Short in the oil pressure transducer cable
Bad Ignition module
Bad E-Stopp control box

[Alan_C]

The door latches for me. Predicted before I even started driving it by another owner. He was right, first latch came apart within the first 200 miles of driving. Do the fix right away as when they break, getting the latch apart is a PITA.

[CobraboyDR]

Or you could just use one of these:

https://www.summitracing.com/parts/sum-220699?seid=srese1&gclid=Cj0KCQjwkIGKBhCxARIsAINMioJovppapOSbgxKfLDyf 6yerYLuU75xSjXFLENHl3AqMSjbiIXMzoWAaAv0YEALw_wcBAt least it is electronic.

The Smith gauges on our SPF's were steam gauges, and oil leaks from the rear of the oil pressure gauge were not uncommon...and messy.

[Norm B]

I have had two failures of FFR supplied items. One may have been partially my fault. The ball pulled off the end of the throttle cable at the pedal end. I was running a fairly strong throttle return spring on my original carb set up. I have had a throttle stick on a different vehicle and may have over compensated. The other failure was the ignition switch. It started randomly momentarily shutting off. Replaced that with an OEM 1965 Mustang switch.

Norm

[SourceLee]

If using a donor EFI fuel tank, the anti-slosh baffle tends to breaks loose. I discovered it floating around the fuel hanger when I upgraded the fuel system. God only knows how long its been bouncing around like that. Mustang forums state it’s a common occurrence with Foxbody fuel tanks. I purchased a new tank and made preventative modifications to the baffle before I installed it. Other honorable mentions:
-Broken J pipe
-Door latch
-Brake light switch
-Upper radiator mounting flange
-Radiator fan relay socket melted

[ggunter]

So far with mine it's been the power steering pulley first, then the oxygen sensor, now a motor issue. 1125 miles.....

[Fman]

After 1500 miles I have had a few things happen:

Melted spark plug wire boot - grounded out causing car to run on 7 cylinders (bought sleeves to go around them for protection)
Leaking fuel pump (O-ring failed somehow, not sure why or how but replaced it and has been fine for 300 miles now)
Drivers door latch broke - door would not open (Did the Kleiner mod on both driver and passenger side and it fixed it)
Speedhut speedometer toggle button broke (Speedhut sent me a new one)
Drivers side valve cover started to leak a little on rear corner (replaced with FelPro blue gaskets)

I did do oil changes at 40,400 and 1400 miles. I did the 1400 mile change after I ran it on the track for the day.

That is about it for me nothing terribly bad but definitely had a few things come up.

[RJD]

Turn signal flasher gave out at 700 miles.

154297


Replaced it with this one. It's an electro-mechanical flasher vs the old one which was thermal.

154504

Does it work? Yes, no, yes, no, yes ....

[richtersand]

Do us a favor and change the tank grommet out now. It is not how careful you are, it is the quality or lack of, in the material. Mine cracked and split. After reading so many reports of issues, I inspected mine. Sure enough, it was splitting.
It was not leaking, probably due to low fuel level, but was scary once in hand.

Anyone have a part number/vendor for me?

[MSumners]

Anyone have a part number/vendor for me?


Ford. F4ZZ-9072-DA