Hi all,
I have just put a new 5.0 v8 engine into my 93 f150 truck. It was just the block so everything was transferred to the new block off the old, bar the parts need replaced. Now I got it timed all good, revved up it sounds right. and had someone help me who knows older cars (unfortunately not efi) That was hard because of a rough idle with what sounds like the fuel injectors clicking and the catalytic converter is red hot (from us holding the throttle open. I have turned the idle screw to a high idle so it stays on for me until i get it fixed... any ideas? whats weird is its the injectors that are new and are under the upper intake. I just can not get it to settle down and purr
I have posted here before but in recent times since the rebuild no one seemed to reply . Any help at all would be greatly appreciated
Dan

 

IIRC....An excessively hot catalytic converter, would indicate a rich condition.

Usually if the headers or manifolds are glowing red, then it's extremely lean.

Check plug wiring and timing as that may be part of the problem.

 

edit... we just took it out for a test. did not make past 20mph really before a thumping noise was happening and it got rough while running too.

 

Timbersteel... I read your thread, what did happen with yours?

 

Just wondering if you pulled the spout connector to time it?

 

This exactly! I forgot to mention that about the timing.

Which thread did you read up on of mine? Lol, sorry ive had a few and can't quite remember what problem I was having.
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Double check your plug wire firing order and be sure there isn't cross firing.

Edit: provide a link to your other thread as well.

Also, what all was done to the block.

 

What is the firing order on the new engine?

More than once someone has gotten a replacement engine with an older version cam that uses the 15426378 firing order versus the newer 13726548. The fix would be to wire the spark plugs with the correct firing order.

 

Using the first firing order you mentioned... we did try the other just in case but nothing out of it.

 

No we did not... where is that located? would that let it run rich too?

 

I believe 1993 and newer 5L truck engines use the 13726548 firing order. At least that is what my Ford manual shows. It should also be listed in the VECI label under the hood. But all of that goes out the window without knowing what cam the rebuilder used.

 

SPOUT location from Subford:


Late timing can cause a rich condition, yes.

 

Whoa, do not run the engine any more, you are washing down the cylinders. Check the fuel pressure..... You will have to use a regulator to lower the fuel pressure. Stock 93 V8 should run around 40psi of pressure. You said you switched to carb? If so that will be your problem. Carb should only need 13-15psi. Hope this helps a brother out.




Never mind, I misread what you wrote. Out of curiosity, which part needed replacing? Ok.
First When you said you replaced the block, Did you mean the Block with the heads on it, or Just a block and you rebuilt the assembly? It's an important question.
Next, Why did you replace the original engine? Same type of symptoms? Just asking.

 

that is most likely your issue. Its not that its running rich, its that the plugs are firing so late that the mixture is not completely burnt before its going out the tailpipe.

 

I actually dont have a way of checking fuel pressure if i am completely honest.
So it was the block with heads. I had to put a new oil pump and screen on, transfer the oil pan. all valves were there so transfer the valve covers and exhaust/air intake manifolds. and of course everything that sits up front. Out of that the alternator, water pump, thermostat, three fuel injectors and all sensors except the knock (hard to get a hold of! which is what a previous thread of mine was asking) were replaced. All vac lines were repaired too while i had the chance of easy access. The new block seemed exactly the same as old

This is the old block and what i got back was the same

 

It was lacking power, and knowing it had 220,000 miles, I need to get to school every day which is a 100mile round trip daily for 1 1/2 years (45,000 miles). Turned out the transmission had vibrated itself to near death, and the rods on the old block had a lot of play on the because of it.