What is this? 1991 Ranger

[BackwoodsSaint]

Ok so I'm working on rebuilding my "new" 91 Ranger 4cyl, it was a California truck and I'm finding a few wierd things on there, lots of empty hose attachements, etc- I just got the truck and I know I didn't remove any of it, when I got it it ran, but had an awful engine noise, hence why I'm digging around in there in the first place- regardless, my question concerns this piece of brass tubing along the firewall just above the valve cover; it is hindering my ability to remove said valve cover so I can inspect the top end of the engine,

what is it and is it safe to remove it?

 

[Mark_88]

It looks like the EGR return pipe that goes into your intake from the exhaust manifold. It is not recommended to remove it permanently but it would need to come off usually to get the valve cover off...

If you must remove the valve cover though, you will need a large wrench to undo the connections on that pipe. I can't remember what size it is, but on mine, since it is not rusted, I can remove them with channel locks. Maybe blast them with some penetrating oil and let them sit for a bit before yanking on them...I've had a few EGR pipes turn into pretzels rather quickly if they are seized to the nuts...

And if the pipe is really copper then it was put on by the PO or someone because they are not copper originally...but I used copper for mine because I didn't have a bender and those 45 and 90 degree bends come pre-made...so it's an easy way to build one.

However...I guess it would depend on what the noise is/was whether you are going to find anything under the valve cover...and even if you did there is nothing that can be adjusted in there...if you hear a clattering or ticking noise then it may be under the valve cover...and may be corrected by some additives to quiet them down...

Otherwise, it could be an exhaust leak or other source.

If you have a video camera or phone that can record videos you can actually record the sound and post it up...many people post their stuff on YouTube but there is a way you can post them on here...if you have a hosting site for clips...but I'm not really sure where you could do that...maybe PhotoBucket or some similar site can let you upload them and then post a link to it on here.

If that is not an option for you, maybe you could describe the horrible sound a bit more...

 

[BackwoodsSaint]

Sounds like you are quite knowledgeable with these 91's, I only started it once and ran it for a couple seconds, i'd have to put a lot back together again to feel comfortable running it.. i kinda jumped in with both feet and started pulling stuff off (definately a dumb move looking back) i was already thinking pretty seriously about starting to put it back together anyways just to hear it again- the best way i can describe it ATM is that it sounded like something was hitting on the oil pan, but the pan isn't bent or anything- the guy that i bought it from said his dad was driving it with no problems, and all of a sudden it started sounding awful, so they towed it back to their house and put it up for sale, i wouldn't say this guy was the most... trustworthy.. guy, definately mechanically ignorant, but i have no real reason to think he's lying, anyways, sound came up suddenly in the middle of driving, didn't hit a ditch or anything, any help would be nice, I'm still sort of new to diagnosing and such- got the valve cover up high enough to look underneath it and the top of the engine actually looks scary clean, can't see under the oil pan because i can't get it down, any help would be awesome

 

[Insanejughead]

With the computer disconnected, does the truck engine crank over?

If it cranks over and makes noise that isn't from the starter, then you may have mechanical problems inside the engine.


Mark is right on the EGR tube, but it isn't something that would cause that kind of sound to come from the engine.

 

[Mark_88]

I'd say I wasn't really knowledgeable about he 91 setup...or even that I know that much about my own 88...but I do know about what's under the valve cover because I made the mistake of taking mine off when I had some valve clatter...only to destroy a good seal on the VC (which can be tricky with these engines) and found that everything was OK and not adjustable...


There is much to learn and also much to appreciate about these little 4 bangers though...they are tough and will give you many years of service if you treat them right...and they are actually quite easy to work on...

Is the noise a constant banging or just occasionally? If it is constant then like Insane said you may have some more serious issues to deal with...if it is sporadic it could be something as simple as the engine bucking and hitting something (could be a loose motor mount)...

Probably worth fixing either way...if not...I know someone looking for a 91 short block (me!) to be rebuilt...

 

[BackwoodsSaint]

Its a pretty consistent awful noise, the top end of the motor is being very unhelpful, like I said, its almost too clean- may consider selling it and doing a v8 swap, but thats more money than I was planning on right now, this was originally going to be a flip and re-sell but now I'm thinking about keeping it, still can't drop a ton on it right now though- what are some popular v8's for swaps and what would be considered a good price? Never done an engine swap

 

[Mark_88]

There is a build forum and a swap forum on this site that you'd probably get more out of than me trying to expound the benefits of a turbo charged 2.3 rebuild...although that is and was one of the most sought after engines...a well build 2.3 with a turbo can get you as much or more than most stock V8 engines...

I'd say one of the most common swaps with these trucks is the 5.0...but I've read quite a few of them on here and some seem more practical than others...like a 4.0 upgrade (needs tranny also) because these trucks came with them stock...so you know everything will fit under the hood without much change other than motor mounts and maybe a transmission support...

There are many build threads so if you are really interested in going that route then there is enough reading material and eye candy here to keep you busy for a few weeks...just put a paper towel under your chin to keep the drool from ruining your shirt...lol

 

[BackwoodsSaint]

The only reason I'd do a swap is if the engine winds up being scrap, otherwise I plan on just fixing it

 

[Charles (in GA)]

If the noise is down low, it could be something as simple as the heat shroud on the cat converter. Mine had a spot weld or two break and started rattling, very annoying, I used a very large worm type hose clamp and went all the way around the heat shroud and cat, tightened it and stopped the noise, that was 8 years ago.

Charles

 

[BackwoodsSaint]

I'm 95% certain it's an engine noise, I know its not coming off the cat

 

[BackwoodsSaint]

*update* I plan on putting it back together this weekend and running it just to get a better feel for where the sound is coming from, wish me luck

 

[BackwoodsSaint]

Ok, so its back together, aside from needing a new starter solonoid (have to jump across it with a wrench) I believe I may have thrown a rod, time to start really digging! Will post a video or a link to video later tonight

 

[stuntsunltd.]

EGR tube

This appears to be a factory EGR tube wich means it should be made of brass and not copper. Another easy thing to check would be to gently pull back the cloth around the tube (it acts as a heat sheild) and see if the tube has any breaks or holes that could cause a leak. Its very easy to destroy these Egr tubes and if they leak they can potentally make a hell of a racket. If the previous owner removed the Egr to get the valve cover off or even removed the exhaust manifold for any reason there is always a possibility that the Egr tube was damaged in the process. Also I believe the size wrench used to remove the Egr tube is either 1 1/16 or a 1 1/8 but be sure tu use plenty of wd40 or penetrating oil on the threads an dreally allow time for it to soak in good. Best of Luck.