Nitram1967

Member
Dec 13, 2020
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1
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Germany
Hi everyone. Im about to restore a 67 Mustang with a 5.0L H.O. engine from 1993 Fox. Its my restomod. Ive read a lot of vacuum leaks and engine problems... to my set up. Ive got the original mainfold intake and the original alternator on this engine. Nothing else. So my question:
What vacuum tubes are really important for a good running engine?
Which new parts would you install ore buy? Like new air controll ore pcv valve?

The engine runs but all vacuum tubes are closed with a screw at the end. I dont think this will work properly.

Thanks for youre help. Hope my english is ok.
Greetings from Germany☺
 
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Well, some info is needed, running efi or carb
If efi, what wiring/computer
If carb, what intake carb
Power brakes, trans type and are the heat/air controls vacuum or still cable like a 67
Other stuff too but this is a start.
Also this may end up in the classic forums, a decision on that later.
 
Im living near to Hannover where the Airport is.
Its like i got everything original from a 67 Mustang exept for my engine. There is nothing more to see exept fir the alternator. Someone build it like that. Got the original 93 engine cable and computer. The intake says 5.0 H.O on the top so its the original intake. Got some power brakes but they are from a 67. Transmission is a 5 gear hand. A/C system is from a 67. 7Rest of all is like a 67 mustang i think. The 5.0 had very hard cold start problems. I dont know if maybe a part is damaged like pcr ore something. I would buy new parts from cjpony ore lmr. And again.. the vacuum tubes are conected to nothing and are closed with a screw. I love this engine it sounds so awsome and i want to have it running as best as im able to

Thanks for reading this ☺
 
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Alrightythen, we got someplace to start, some things you need like vacuum to the fuel pump regulator, if it has power brakes and pcv,
Some 67 had tilt-a-way steering that had a vacuum source but it was a rare option. That should cover the vacuum part now on to tougher stuff.
Inspect the wiring harness looking for the test port, that is where the scanner plugs in to get info from the computer, also what type of fuel delivery system does it have? What computer?
 
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Most vacuum lines on modern engines are for things related to emissions. IE, charcoal canisters, EVAP solenoids and the like....they are not needed for the engine to run. The only 2 critical vacuum connections are for the fuel pressure regulator, and to the brake booster if the car has power brakes, EGR is next on the list, but not critical for the engine to run, you can trim down a lot of the vacuum connections in an old car that isn't required to have the emissions equipment(check your local laws for what equipment you must have on an engine swapped vehicle)
 
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Im living near to Hannover where the Airport is.
Its like i got everything original from a 67 Mustang exept for my engine. There is nothing more to see exept fir the alternator. Someone build it like that. Got the original 93 engine cable and computer. The intake says 5.0 H.O on the top so its the original intake. Got some power brakes but they are from a 67. Transmission is a 5 gear hand. A/C system is from a 67. 7Rest of all is like a 67 mustang i think. The 5.0 had very hard cold start problems. I dont know if maybe a part is damaged like pcr ore something. I would buy new parts from cjpony ore lmr. And again.. the vacuum tubes are conected to nothing and are closed with a screw. I love this engine it sounds so awsome and i want to have it running as best as im able to

Thanks for reading this ☺
That's great, Sounds like a nice car. I would check with the Ford Gods here because it sounds like you have some serious problems. A fuel injected motor should fire as soon a fuel is force fed. How is the battery ang charging system? Can you check these things or will you need to use a shop/garage? I have a brother that lives in Hannover as well, what a coincidence! I also have a sister in Manheim. After COVID is over I am going to visit them.
 
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Define "cold start". Do you mean starting in cold weather? Or do you mean first start of the day regardless of temperature?

If it has trouble while starting in low temperature, that is a symptom of the engine not getting enough fuel to compensate for the cooler denser air charge. That can be anything from a failing fuel pressure regulator or pump, to a bad air intake temperature sensor.

If it has trouble first start of the day regardless of temperature, but starts fine otherwise, its likely a problem related to fuel pressure...the fuel system slowly bleeds off pressure the longer it sits, again, the regulator is a possible culprit in this case....or since its an EFI retrofit its possible the rest of the fuel system is not well designed to hold pressure like factory EFI cars are...many factory cars have what they call "fuel accumulators" which prevent fuel bleeding back into the tank and emptying the lines after shutoff....also, it depends on how the fuel pump is wired as to whether the system pre-pressurizes before you start the engine.
 
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Good morning from Germany! so.. first i checked if there is a vacuum at the steering.. no. Then i looked at LMR what kind of power brake booster the 93 has got. I only got the original brake system from 1967 so there is no chance for vacuum...... am i right that the vaccum from the power brake booster is no.1 for necessary vacuum? I would chance it with a 93 brake booster!

I coulnd find a test port at the cable tree.. computer is original.
Fuel pump runs! Checked it. Its a very big one without any tune up name so i think its original. New one? Can you recommend something? I would spend money for new good parts if needed.

I dont have any laws because of emissions because its a old car. Thats good. So when i would connect the fuel air regulator and the power brake system with my vacuum system.. the engine would run good?

Cold start problems where like.. it doesnt mater if its cold ore warm.. the first start after standing takes 10 min befor the engine really starts.. But then its ok.. new sensor?

I would make a list for new parts.

Cant check charging system.. maybe its damaged. Visit youre brother would be an option!

Thanks for helping me in my situation!!!
Regards :)
 
Just because a fuel pump runs doesn't mean its good....a fuel pump can run badly for quite awhile before failing. The first thing you need to do is test the fuel pressure at the fuel rail with a pressure tester....for a 5.0L motor it should read somewhere between 39 and 43 psi(not sure what units of measurement you use in Germany for fuel pressure but in the US its measure in pounds per square inch). If you have less pressure than that, its either the regulator or fuel pump that is failing...if you have at least that much pressure its something else.
 
2 Discbrakes in the front but original 67 break cylinder system and yes im using the correct engine harness for my engine.
Its an old fuel pump.. maybe there is one mistake but im checking the pressure. Also i couldnt find the pcv vacuum connection.. there is only the tube from mainfold intake to pcv..

So what can i do without the vacuum from the power brake booster?
 
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Man, you could use a vacuum tree, although the pcv needs a line by itself, you already have that so the issue is the booster, pull the upper intake off and give us a pic of the underside of it, there should be vacuum nipples under there.
 
Last one is the fuel pump
 

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Well honestly I just kinda skimmed over those pics, I'll get back to that in a minute, I believe you need to rethink the fuel pump, that pump will work but the optimal thing would be a in tank pump, I believe they would be more efficient and last longer.
Now about the vac lines,, let me go back to the pics, be back in a minute :leaving:
 
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Ok, just a couple things to adjust in my opinion
Make sure the pcv hoses fit tight, the routing looks good but you may want to shorten up the hose from the intake nipple to the pvc valve, you can also use a pcv valve with a 90* nipple on it so the hose has a straight shot to the pcv valve. Rockauto has it, another trick is to use small black zip ties at the nipple to secure the hose tight to the nipple.
Now about the vac line to the booster, the pic of the back of the intake shows two nipples, one has a cap on it, run a hose from there to the booster and cap the other one and you should be good. Use new hoses and make sure the screen under the pcv valve is clean and the grommet it fits into holds the valve tight, you can get new stuff from rockauto or maybe a local parts store,
 
I will pay a lot of attention for the new tubes and caps and correct routing! I will think about the new in tank pump. Checked the pcv.. very dirty and grommet was not very tight. Will change that.
And i learned a lot of how the vacuum parts work together.
Now i finally got a plan for my engine and i want to thank you all :)
 
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