kishy's 1991 Grand Marquis

[DerekTheGreat]

Those you have to reset once they pop. These are great for the little critters:
Uhlik Repeater Traps | The #1 Live Repeater Trap For Rodents

[kishy]

Alrighty, with the road trip (http://www.grandmarq.net/vb/forum/si...e-dragon-2024/) being complete and both the car and I having made it home fine, there are some findings over the course of the trip that should be evaluated or at least noted.

First, bringing over the stats as noted in the road trip thread:

States visited or driven through: MI, OH, KY, TN, NC, VA, briefly WV, MD, DE, NJ, PA.
Worst drivers found in: VA once again! They found new ways to be annoying this time, but they were still the worst in really obnoxious ways.
Tolls paid: about 10 USD but one of the booths was bill-by-plate only so a bill may or may not appear in the mail for an amount I will not know until/unless it does
Distance driven: 2403.5 miles or 3868.1 km per trip odometer
Fuel consumed: 125.8 US gallons per actual fuel station pumps
Fuel economy: 18.91 US MPG average across trip per actual calculation of actual fuel vs odometer in each leg of the trip. Low 14.4, high 22.4
Highest elevation reached in the car was 6320 ft at Clingman's Dome parking lot (where we proceeded on foot to 6641 ft at Clingman's Dome itself).
Lowest elevation would be essentially zero in Atlantic City.

Prior to this road trip and the work done in lead-up to it, this car had last seen regular use in 2016, before it handed off daily driver duty to the '84 Town Car. That was a relatively extended period of downtime but none of the car's needs before the trip were particularly severe, so it didn't seem like a big gamble to me.

Observations through the course of the trip:

• Over the 2400 miles, it consumed 1.5 litres of Rotella T6 5W40 synthetic HDEO. Replacement oil was added in 0.5 litre increments at fuel stops where I checked the dipstick, and lost oil was replaced with more of the same T6.
  • When the car was parked in 2016, it was already a known oil burner. I don't have an exact figure on oil loss but this car was always more of a burner than a leaker once I addressed the intake and valve covers forever ago. Maybe a litre per change interval, and regardless of oil choice, always changing at 3000 miles / 4800km.
  • This car was always observed to absolutely drink 5W30 while showing acceptable loss (the 1L/4800KM figure) with 10W30. It was also observed to absolutely drink synthetic while showing acceptable loss with conventional. Accelerated loss with a 5W synthetic oil, especially on a trip with a lot of sustained hill climbing, sustained downhill engine braking, and a lot of wide open throttle was not a surprise and does not concern me.
  • As the car feels pretty good for power, to address oil loss I would probably just pull the heads and do valve-related stuff (guides, seals). It is worth noting that this does have a pretty noisy bottom end at cold startup (suspect piston slap) and prior to the 5W40 oil going in, it did have no oil pressure at idle when good and hot. But the 40 weight stuff is apparently filling the widened tolerances adequately and pressure stays up now. So it's fair to say the bottom end needs love but it's maybe not a concern yet.
• The car continues to exhibit aggressive spark knock in conditions which it did 10 years ago, which I never successfully chased down, and still find myself clueless about. 10 years ago, I found that running premium made it go away, but there are some considerations:
  • The transmission behaviour causes the engine to run at much lower RPM than any of my other Panthers in conditions that are prime candidates for spark knock. E.g. hot engine, low RPM, try to get kickdown out of OD, get knocking until the trans performs the shift. Too much load relative to current RPM in those conditions.
  • But, regardless of the transmission behaviour, with a properly hot engine it will also knock at mid-throttle acceleration in a lower gear at higher RPM. It won't do this consistently, just sometimes, and is highly dependent upon exactly how far into the pedal I am.
• The transmission behaviour outlined earlier in the thread is infuriating, but manual 3-4 operation makes it tolerable.
  • TV is set high, in the sense that there is not much more cable available to use. Current gauge readings unknown.
  • The squeal sound before a shift, most notable in 2, suggests a problem.
  • The 3-4 shift is not an immediate "thunk" like my others, it's more of a 2-stage "ka-chunk" with a little gap in the middle. There is no shift flare or slip on any shifts, however it very very very rarely will not actually engage drive until I bump the gas pedal slightly.
  • Transmission behaviour has not changed over the course of the trip. It remains as it was before the trip, which is the same as it was 10 years ago. There is clearly something broken or leaking somewhere but not enough to prevent it working anyway.
• The brakes were quite smooth at the start of the trip and are now quite grabby, most notably the rears feel like something weird is happening.
  • The car still stops very well, but there is now a "tip over point" where the brakes go from "normal slowing down" to "we're stopping NOW" rather suddenly. This can be mitigated with the pedal but it isn't how it's supposed to be.
  • Also, on the trip, what I initially thought was the smell of burning plastic but later realized was hot brakes did come up a few times, and I do not believe it was from the front brakes. I did look for, and could not locate any melting or burning plastic or rubber which could have been the source of the smell, and my friends immediately thought it was the smell of hot brakes rather than plastic.
  • The $6 brake pads did shed a lot of dust and the HPPs up front are filthy now.
  • I plan to take the drums off and check for axle oil leakage, because that could explain the drums getting a little weird.
• The suspension on this has exactly the feel that I want out of it, which is interesting because I once found this car entirely too firm, particularly after putting the KYB Excel-Gs in it, which it still has today. Maybe as they've aged they've softened a bit. They do seem to be doing some damping but that "sideways axle hop" over certain sudden bumps like railway tracks is creeping back into the picture.
  • The rear sags too easily with too little weight. I believe this has CC817 cargo coils, so maybe a stock replacement single rate spring is the right option.
  • Aesthetically, the front could due with dropping a very tiny bit, but I might change my mind about this after the rear goes a tiny bit higher. Perhaps 1/4 or 1/8 of a coil cut, nothing more. It has Moog 8652 springs up front. This car did at one time have the Speedway 925 springs up front and I hated how it drove more than words can express. Looked great, though.
• The leather seats are a substantial step down from the flocked/velour seats when it comes to cornering on twisty roads. Your clothes kind of interlock with the velour-finish seats whereas you just slide all over on the leather.

Zero regrets about taking this car. It performed well, got better mileage than the wagon did, and was comfortable (except for the seat concern as noted above). I do think the 90+ cars have slightly better driver ergonomics than the older boxes, as well (seat angle and position vs steering wheel vs pedals).





(yes, I'm over the line, but note it's the line where you don't mow down oncoming bikers as a penalty)

[Arquemann]

The suspension on this has exactly the feel that I want out of it, which is interesting because I once found this car entirely too firm, particularly after putting the KYB Excel-Gs in it, which it still has today. Maybe as they've aged they've softened a bit.

Last year I put Excel-Gs in the back of my '85, I certainly found them a bit too harsh. I don't understand how so many jizz over the Gas-A-Justs which are supposedly even firmer. Though the random brand NOS shocks I put in the front are kinda sloppy and definitely could do being firmer.

Nice pictures.

[gadget73]

A tidbit I can offer, I saw a puff of blue-grey oil smoke out of your left tailpipe leaving the diner. Valve seals would be a fair guess for that.
As for the squawk noise, having a gander at the 1991 Mark VII manual's section on AOD symptoms

mushy/early all upshifts pile up / upshifts
fluid level
low TV pressure
low main control pressure
valve body bolts loose/tight
valve body valve throttle control valve sticking
governor valve sticking


there is nothing about noises, but I remember you mentioned it won't hold 2nd
closest its got is soft/early/mushy 2-3, and its all the same stuff except "direct clutch assembly burned/worn"


there is a mention in here about "transmission noisy - valve resonance". Not sure if thats the buzzy noise the AOD does sometimes but it says
fluid level
improper band od clutch application, or oil control system
cooler lines grounding
dirty/sticking valve body
internal leakage or pump cavitation


just based on all that I think I might be looking at the valve body for issues. Seems to be the other common thing. If you happen to have a spare late model valve body around, maybe go through that and make sure its all clean, assembled right, and nothing is sticking and swap the whole thing.

[87gtVIC]

Awesome photos! Looks like a blast.