Introduction and...advice.

[4 Jaw Chuck]

Hello everyone, just joined and wanted to introduce myself. thumbs_u

I've read a little of the past postings and FAQ's regarding problem(s) my Dad's 94 SHO-atx is exhibiting. (BTW he's 81! ) It appears to be a few common problems put together that are the cause, listen to the symptoms and diagnosis so far;

The car is pristine except for a few blisters on the trim (my dad loves this car and washes it to death) it has 160 000km on the odo and is on the original trans etc (no problems so far). The engine was replaced in 95 by the dealer-no charge, dealers wife owned it before my Dad. wink Everything works, even the sunroof doesn't leak! It has been babied and looks it.

The car right now appears to have a shot thermostat (stuck open), leaking rad (pinhole) and a light tapping coming from the belt side of the engine. From the postings I have read this engine is due for a sensor change as well as a valve adjustment and I might as well do the CPS and water pump, idler bearing etc. etc. There is no leak at the water pump...yet.

The car will not warm up and has refused to start after hot shut down, it felt like the timing was way out during cranking. It restarted minutes later (CPS?). The check engine light comes on when the temp does come into the normal zone but goes out after a period of time. It will cool off at idle. Performance is still excellent, mileage sucks of course(thermostat). I have not read the codes yet. Curiously the front rad fans operate even though rad temps are only warm and no pressure is evident at the cap (I've removed it to check and stick a finger in)? Is this normal? The tapping concerns me because I cannot locate the source even with the stethoscope, it is not regular and does not appear to be the water pump, idler bearing, or the valvetrain. It does seem to emanate from the belt side of the engine though?

So I guess my question is, since the time is ripe to replace all these components now and do a complete go over of the engine as preventative maintenance should I pull the engine out from below with the subframe and work on it unimpeded by limited access? Or should I replace these components from above and scrape my knuckles, I don't have a lift but I do have a good 1 ton jack?

The engines valvetrain operates perfectly silently (had a stethoscope on the valve covers), do I still need a valve adjustment at this age? We are assuming the previous owner did the 60 000 mile adjustment. What might the tapping be? It does not appear to be rod or crank related?

What are the advantages of placing the CPS closer to the crank at 0.024"? If I am replacing it anyway what are the effects? Should I buy the Ford components or aftermarket? How much should I expect to pay for parts to do this job? Ford parts? Aftermarket? Experiences?

As you can see I want to do this right and only the best for the old man, this will probably be his last car. I'm a machinist so I have the tools and skills to do the job, any hints? Am I on the right track?

Thanks for the help in advance.

Great site BTW!

 

[Rob94]

I can answer your tapping question. I had the same tapping sound, and replacing the timing belt got rid of it. Belt stretched to the point that it was hitting the timing cover.

 

[projectSHO89]

The ATX uses an automatic tensioner as opposed to the MTX's fixed tensioner for the timing belt. If the noise is coming from the timing belt, that means that the belt would have to have stretched AND the tensioner has failed. Possible, certainly, but not as likely. My guess would be rod bearings or crank cancer, depending on the area of origin for the engine.

At 160K km, your car is due for a new timing belt anyway. Good time to perform the rest of the suggested front end work including new seals, a water pump, a new crank sensor (your's sounds flaky), inspect the crank for cancer, etc.

The front end work can all be done without removing the engine from the car. No need for that much extra work.

The thermostat is a 15-30 minute job. If you do it at the same time as the water pump and the radiator, you only have to mess with the cooling system once. I would also replace the temp guage sending unit, it's only a coulple dollars.

Get the codes from that CEL. That will give the reason for the light.

Welcome to the forum! Hope your dad enjoys the SHO for many years to come.

Steve

 

[4 Jaw Chuck]

Thanks Rob and Pro89, your input is much appreciated. I've phoned around locally for a replacement rad and all that seems to be available is a factory replacement rad for $267 Cdn (good price?). Is there a brass replacement available for this car? The guy I spoke to said to use a 7 pd cap to reduce stress on the cooling system, since the factory cap is 16 pds this does not sound right to me since cooling system capacity would be reduced from 260 degrees to 240 degrees, what do you guys think? bs or not?

How does "crank cancer" affect this car? I did not know they had crank problems?

Thanks again, Chuck.

 

[sdpatt]

Stick with the 16 pound radiator cap. Yes, you are due for a new timing belt and new acessory belts. Check the idler pullies for free-spinning bearings while you have everything apart. Your climate is much harder on components than I am used to seeing.

What is the frequency of the tapping from the front (passenger footwell side) of the engine? Is it engine rotation speed, 1/2 engine rotation speed or other?

You need to ensure that the plugs have been replaced and were they replaced with the correct Motorcraft AGSP32PP plugs. Hot start failures sound like either a weak spark or low fuel pressure problem. Check those EEC codes. Learn how here.

 

[4 Jaw Chuck]

Thanks Sd, the tapping is not regular at all and does not seem to be tied to engine rpm. I will check tonight to see if it is in fact related to engine rpm. If I could describe it I would say it sounds like someone putting up a picture in another room of the house and does not repeat regularly although it is persistant and does not disappear. My first thought was an accessory belt/timing or bad water pump bearing, my stethoscope testing did not single any of these as the culprit. My first instinct when I heard it was rod bearing but it sounds too weak and irregular for me to be positive in this diagnosis.

I should mention the car has never been abused, actually if it has seen more than 1/2 throttle since my Dad has owned the car I would be surprised.

Thanks for the help, Chuck.

 

[luigisho]

With that many miles bearings may not be out of the picture. A good all over front and top end maintenance would be a good idea at some point. The rod bearings can be accessed and checked (either remove to inspect or just plastigage) by dropping the oil pan and windage tray. Just some food for thought.

 

[pjtoledo]

,,,,,,,,What are the advantages of placing the CPS closer to the crank at 0.024"? If I am replacing it anyway what are the effects? Should I buy the Ford components or aftermarket? How much should I expect to pay for parts to do this job? Ford parts? Aftermarket? Experiences?,,,,,
:[/QB]

The crank sensor gap is not all that critical. You can't alter the timing by screwing with it. The actual Crank Position sensor has a cut out that allows a metal vane to rotate through it. You simply need clearance on both the outside and inside of the vane. Since you are a machinist, what's the best way to keep your lead screw true?

Perry Toledo,Ohio

 

[4 Jaw Chuck]

Keep it clean and centered wink Gotcha.

-UPDATE-

A cold start pretty well clinched the water pump as the culprit making the tapping noise, sounds like balls out of their cages in there.

Whew! I don't even like talking about having to do rods and mains on this car. Looks like an easy fix so far, the rad fans coming on at such low temp is weird though. Is there a sender for both dash gauge and rad fans, which is which? Why is plug selection so critical on this engine?, or is it just one works best?

<small>[ December 17, 2002, 12:13 AM: Message edited by: 4 Jaw Chuck ]</small>

 

[projectSHO89]

The cooling system has two sensors (and a third if you have ETAC). Both are mounted adjacent to the thermostat. The frontmost one is a single terminal sending unit and only goes to the TEMP guage on the dash. The other (ECT sensor) is aft of the thermostat, has two terminals, and is the one that the computer uses to detect the coolant/engine temperature.

Radiator fans should be on whenever the AC compressor is engaged. This includes when the DEFROST function is selected. The computer turns on the fan(s) when it detects an engine temperature of around 210-220 F. The fan relay(s) is (are) located in the relay module that is mounted on the top radiator support under the plastice shield with the emmissions labels. Look for a black box with a large letter printed on the label, such as J or M.

The Motorcraft plug specified on the emissions label is the one to use unless you know exactly what you need and why (ie, NO2). That plug fits and works perfectly and has proven to be the best choice for most drivers. This plug was the original specified for this engine and has the correct double platinum tips and correct height to mate with the Motorcraft plug wires.

Many of the parts for the front end service are available for far less at AutoZone or online than those at the dealership. Scott Patterson has posted a list many times of the parts suggested with pricing and sources for these parts. His post should be easy to find with the SEARCH feature.

There have been no reports of significant problems with aftermarket water pumps, sensors, seals, belts, etc.

in regards to "crank cancer", here is the text from one of the members of the shotimes mail list (bjamesjr) that describes it well along with a "how to diagnose" procedure:

1. Pull the top timing belt cover loose enough that you can bend it a little
and see the timing belt and/or timing gears.
2. Rotate the crankshaft slightly back and forth. On mine I did this by
jacking up the right front corner of the car, putting the car in 5th gear,
and turning the right front tire with my hands.
3. The timing belt and gears MUST move perfectly in unison with the
crankshaft. If there is any movement of the crankshaft before the belt and
gear "catches" and starts moving, then you likely have a worn crankshaft
timing gear, otherwise known as "crankshaft cancer".

Anyway, what can happen is that the lower crank gear can become loose, as if
the harmonic balancer bolt was not properly tightened when it was
reinstalled. With the gear loose, it vibrates back and forth against the
woodruff key in the crankshaft and gradually wears the key and the groove in
the gear until the gear can move back and forth quite a bit, hence the
"click, click, click" noise that you hear.

Hope this helps.

Steve

 

[4 Jaw Chuck]

This all makes perfect sense now, thanks for helping out a SHO newbie. Hopefully the crank has no "cancer", is there a common fix for this problem that works besides a new crank or brazing up the splines and recutting?

I cannot think of a simple durable fix for this problem?