first post

[jim]

Howdy,

My Mom can no longer drive her 1987 Grand Marquis white two door with 59k miles, so reconditioning is now another project for me. Currently at the top of the list is a hanging rf wheel, a tapping engine sound which I'm guessing is sticky lifter, and an intermittent miss when hot and under load. Could the tapping be caused by two leaks in the air pump system? Do those emission things pulse or flow?

[85crownHPP]

I'm not sure if the smog pump pulses or flows air into the pipes, but you definitely hear and feel poot-poot-poots of air coming out of the seemingly empty nipple on the air pump, that's normal. How does the tapping noise respond to rpms and load? If it is a sticky lifter, sometimes and engine flush will quiet them down. The load-miss could be bad plug wires, or any other ignition parts. Do you know its tune-up/service history?

The car sounds sweet - what color interior? Any pictures?

[VicCrownVic]

Welcome!

[johnunit]

I'm not sure if the smog pump pulses or flows air into the pipes, but you definitely hear and feel poot-poot-poots of air coming out of the seemingly empty nipple on the air pump, that's normal. How does the tapping noise respond to rpms and load? If it is a sticky lifter, sometimes and engine flush will quiet them down. The load-miss could be bad plug wires, or any other ignition parts. Do you know its tune-up/service history?

The car sounds sweet - what color interior? Any pictures?

what he said.


Glad to see you're carrying the torch with your mom's car. These are a great way to get into the classic car hobby, as they're still relatively cheap and easy to repair, but are getting more looks and thumbs up by the day. Two door merc's are one of the rarest breeds, too.

[89TownCar]

Two door MGM?! I am jelly, wanna trade?

[jim]

reply

I'm not sure if the smog pump pulses or flows air into the pipes, but you definitely hear and feel poot-poot-poots of air coming out of the seemingly empty nipple on the air pump, that's normal. How does the tapping noise respond to rpms and load? If it is a sticky lifter, sometimes and engine flush will quiet them down. The load-miss could be bad plug wires, or any other ignition parts. Do you know its tune-up/service history?

The car sounds sweet - what color interior? Any pictures?

Thanks for the reply. One air pump leak is from the secondary check valve nipple rotted away, which I'll try to reseal with duct tape, while another is in the down pipe just before the Y split to the driver side cat. conv. The miss develops after about a half hour of stop and go warm up. I have service records from day 1 (9-87), and if I recall, tuneup stuff was several years ago, but only a few thousand miles. The records aren't where the computer is, so I'll check later. The interior is tan cloth. pictures will eventually be posted after clean up.

[Toploader]

Jim,
Welcome to the asylum from another GM Tudor owner! As yours is the last year of manufacture, you have the rarest of the rare!

[johnunit]

Thanks for the reply. One air pump leak is from the secondary check valve nipple rotted away, which I'll try to reseal with duct tape, while another is in the down pipe just before the Y split to the driver side cat. conv. The miss develops after about a half hour of stop and go warm up. I have service records from day 1 (9-87), and if I recall, tuneup stuff was several years ago, but only a few thousand miles. The records aren't where the computer is, so I'll check later. The interior is tan cloth. pictures will eventually be posted after clean up.

While I've since replaced mine (<$20 from rockauto), I fixed my leaking check valve by sanding away the rust and smothering it in JB weld. That may be more permanent.

[jim]

I didn't find any ignition tune up records, so perhaps throwing some parts at it will cure the hot, under-load miss. Would plugs and wires be a proper first round? Yesterday was consumed with a right front caliper replacement due to a hanging wheel. The rotor looks like it's a replacement candidate from "hot spots," but it seems integral with the hub, so I may stretch a few miles more before an expensive part replacement. I'm thinking of pulling the air pump and trying for a shorter belt. Has anyone done this, and if so, what size belt worked?

[johnunit]

Good rotors are like 50 a piece.

[sly]

the rotor/hub assembly isn't spendy, but with new bearings and grease might be a bit more than you really want to spend depending on your financial situation. If it's not warped, don't worry about it. Plugs and wires may not be all that bad... take the hood bulb out and open the hood at night with it running and spray a mist of water to see if the wires are bad (you'll see little arcs all over the wires if they're bad). Check the vacuum lines for cracks and broken lines first as that's usually the main issue that causes crappy running in these cars.

I had to pull my smog pump when it seized. I put a 56inch belt on. a 56.5 or 57 inch belt might work better to get over the pulley without the shenanigans I had to go through.

[jim]

Sly, thanks for the tips about wires and vacuum lines. I-I-R-C, I can spray some ether or something on the vacuum lines to detect a leak if it results in an rpm bump. I broke the under hood bulb trying to remove it, so that's not a worry.

[sly]

propane works for the vacuum hunting too... just be ready with the valve to shut it off if needed.

[jim]

I'm replacing the steelies with turbines and just noticed the turbines are one half inch wider. Thus the larger tires (225/70/15) should fit better. The locking wire wheel covers will soon be surplus. What are they worth?

[Mainemantom]

If the wire wheel covers are in mint condition, $100 for the set would be reasonable. Much more and you will be sitting on them for awhile.

I'm replacing the steelies with turbines and just noticed the turbines are one half inch wider. Thus the larger tires (225/70/15) should fit better. The locking wire wheel covers will soon be surplus. What are they worth?