New Rover owner...a few problems

[TigerDan]

Hi, just joined up. I have a '91 Range Rover that I just purchased day before yesterday:




It has a few issues that I'm working my way through and I have some questions.

The CEL is on and I have to get that taken care of before I can smog it. It's throwing code 45, for the right O2 sensor. I first checked the wires and found the plug seemed a bit loose. Pushed it together till it clicked, cleared the code and went home happy. Yesterday morning the CEL came on again, code 45 again. I got to poking around under the hood and found a vacuum line that had been chewed through by a 'possum that took up residence under the hood before I bought it. (The PO had to repair some chewed wires so he thought he'd missed something, ergo the CEL...) I fixed the line thinking that the vacuum leak was triggering the code. Cleared the code, went home happy. This morning it came back yet again.

Now my question...this thing has a fairly bad exhaust leak where the right side manifold connects to the exhaust pipe (the pipe has separated from the flange...I'll have to pull it and weld it) Is it coincidence that the exhaust leak is on the same side as the sensor that's causing a code, or can an exhaust leak ahead of the sensor trigger a code from the sensor?

Maybe it's simply time for new sensors. It's got 184K miles and I don't know if they're original or not...

Now on to my other question: I get an annoying vibration/rattle from under the front of the vehicle, I've determined that it's caused by the front driveshaft rubbing on the sway bar. How much clearence is there supposed to be between the two, and what could have caused the front axle to move in such a way as to cause this interference? I've jacked it up and shaken and wiggled and inspected and things seem tight, bushings seem fairly firm...I'm thinking that in the short run I'll simply shim the sway bar down and away from the driveshaft, but this has me bugged.

Overall I'm pretty happy with it, for a grand I couldn't pass it up. Needs a heater core and they seem to be pricey, not to mention a blast to install. Lots of little issues to take care of but it's quite drivable as is so I can take care of things as time permits.

This is my first Range Rover, but not my first Rover. I have a '61 SII Land Rover as well as several other English vehicles. I'm no stranger to a wrench and am not afraid to tackle anything on the vehicle. In fact, I'm a moderator on another automotive forum and spend a lot of my time dispensing advice...now the tables are turned and I'm the one doing the asking!

[TSR53]

Welcome to the RN forum! Nice looking RRC.

[J!m]

Replace the sensor. For the cost, it's worth it if you do your own work.

The truck is riding quite high, which may explain the rubbing sway bar. I have my rear sway shimmed to clear the tank guard- no issues with performance.

Oh, yeah. Fix the exhaust leak, although I don't think this is why its throwing a code...

[TigerDan]

Okay, thanks. I'm fixing the leak today, as well as shimming up the front bar. I'll order new O2 sensors.

I thought it seemed to ride a bit high, and the nose is higher than the tail Perhaps the springs were replaced with taller ones as I don't see any other evidence of a lift kit, The tires are oversize and the fronts rub on the radius arms in tight turns, perhaps there were other clearence issues that neccessitated the lift. The PO lives out of state and I haven't talked to him, I bought it from a friend of his down here who was acting as an agent fror him. Perhaps a phone call is in order...

[JSalyer]

RR

Tiger Dan,
That truck has to have a lift(I clicked on your pick and went to your online photos) I wonder if the person installing accidentally put the front and rear springs on reversed!!?? I have never seen any lift with the front higher than rear(usually the reverse is true as the rears are for overload to some degree). See if you can see any decals on the springs still, or take a flashlight and see if you can see a faint grey number(ie 762, 764 etc). I do see the shocks are yellow, indicating OME or Bilsteins. I'll bet money you have a set of rear springs in the front or the person put rear MD's in the front. Anyway get this sorted out, nose up aint cool. Get the springs sorted out and I'll bet your driveshaft issue disappears.

Also, anytime you have an exhaust manifold leaking or cracked get it fixed ASAP, I have seen exhaust valves(in the head) burned or damaged by not properly exhausting the gasses(incorrect back pressure I think)

Cheers,
Jack of Bavaria

[TigerDan]

Thanks Jack. I did take care of the leak already and shimmed the front bar, then painted the wear marks on the bar and the driveshaft. I still have the vibration/rattle and the new paint isn't worn off so I guess that wasn't the problem after all. Still needed to be fixed though...:-D

I'll take a close look at the springs. The nose-high attitude does indeed look strange and could contribute to some odd handling issues I'm experiencing. If I swap the springs front to rear then I can take the opportunity to really get in there and poke around; the vibration seems to come from the left front.

[leadoff]

Dan -- I've been having big trouble sealing the right (passenger side) manifold to downpipe exhaust connection ever since I've owned my 1990 RR County. It leaks on the edge closest to the battery. The OEM washers had been left out of the stud & nut assembly, so I don't know what they are supposed to look like: I ordered new genuine nuts & washers, but the ones I received from RN weren't correct. I've been using a standard 8M hardened metric lockwasher. Please advise, anyone.

Also, I've had difficulty getting the gasket over the first 2mm of the studs without damage -- one of the studs is slightly bent I supposed. It should fit easily. If I could identify the bent stud, any advice on a gentle tweak so I dont crack it, anyone? I don't want to get into replacing those if I can avoid it, but perhaps this is the source of the chronic problem. Please advise, anyone.

Thanks,
TJ 1990 RR County

[J!m]

...the vibration seems to come from the left front.

Check the CV joint and associated parts on that side.

I had bad splines on mine (24 spline HD 110/130 set-up) and replaced the enire axle/CV/drive flange assembly on that side.

Also, be sure the end float is correct for the axle stub sticking through the drive flange (on both sides actually). If the float is too great, the CV axis of rotation will not be alligned with the swivel pins axis, leading to a very disturbing (and ultimately expensive) noise. This is most prevelant while turning, but can be heard all the time if the wear has already occured.

Just a thought for you...

[TigerDan]

Thanks, as it happens I was in there today as the left wheel bearing was a tad loose. I don't know how much axle end play there's supposed to be, but I'd guess I've got at least .060 maybe more. The splines are a tad sloppy as well (on both sides) and the majority of the slop seems to be in the drive flanges so it looks like those are on my soon-to-be-replaced list.

Jack;
I got underneath and took a good close look at the springs today. Here's what I found:

No visible ID on the front springs, but with the vehicle at rest on all fours they measure 14.5 inches tall. The rears measure 12.5 and have a tag on each with OME-764 printed on them. Is this a front or rear spring?

Rear shocks are Bilsteins and appear to have been on there for a while, fronts are OME (Old Man Emu?!) and appear fairly recent.

[J!m]

I don't have my manual handy, but I am quite sure 0.060" is over SIX TIMES the maximum end float (maybe 12 times over), and likely a good cause for your noise. The bad splines don't help, but usually its the rears that make all the drive line clunking...

When you order the RN replacement splines (as shown on this board recently) ask for an assortment of shims and new snap rings. Use a magnetic-base dial indicator and check the end float (you need a bolt to go into the axle end to pull and push as you check).

I think the end float is supposed to be 0.002"-0.005" but I'm not 100% sure on that. When you call RN they can provide you with the data you need.

If you don't have an indicator handy, set the end float as tight as you can by hand and still get the snap ring in securely. It could be written as 0-0.005", but if it's actually zero,you can't secure the snap ring properly...

Obviuosly, check both sides and adjust. The new drive flanges will require re-shimming.

[JSalyer]

OME springs

TigerDan,
Look below, you will see you are good to go on the rears, but they have installed the wrong ones in front. They probably installed rears in the front too. This is a typical way of achieving 3" of lift in Rovers, but they didnt do it right. If you cant tell what they are, order two new fronts from the chart below to match them correctly. Go on the ExpeditionExchange website(https://www.expeditionexchange.com/ome/indexsprings.htm) for good explanation of all the possible combos for OME springs. The vibration is from the horrible pinion angle you have up front and it will lead to ujoint failure eventually.

[CENTER]


Part No.
Axle
Rate (lbs./in.)
Recommended
Application
Length (DS)
Length
(PS)
Resulting
Lift

760
Front
180-250
Light Duty (under 0-50 lbs.)
15.1"
14.6"
2"


FONT=Verdana]761 [/FONT]
Front
200
Medium Duty (50 lbs. to 110 lbs.)
15.7"
15.4"
2"

751
Front
230
Heavy Duty (110 lbs. to 250 lbs.)
15.3"
14.9"
2"

766
Front
280
Extra Heavy Duty (220 lbs. to 350 lbs.)
16.6"
16.6"
3"

764
Rear
220
Medium Duty (unspecified)
16.9"
16.5"
2"

781
Rear
290
Medium/Heavy Duty (unspecified)
16.7"
16.3"
2"

762
Rear
300-340
Heavy Duty (220 lbs.)
16.5"
16.1"
2"

763
Rear
360
Extra Heavy Duty (440 lbs.)
16.5"
16.1"
3"
Cheers,
Jack of Bavaria

[JSalyer]

Crap, all that work, lost the reply!!

Dan,
Goto

https://www.expeditionexchange.com/ome/indexsprings.htm

view the article on spring usage and type......

Jack

[TigerDan]

Jack, I had found some specifications for the OME springs after I posted and discovered that the 764s are indeed rears and was just poking around on the site you linked. It seems that the 764s are not optimal for the rear but should be okay for my needs at this point. So now I guess I need to figure out just what they did put up front. I'll pull one out and measure free length and rate just for the fun of it.

BTW, I see you're in Bavaria, are you anywhere near Wurzburg?

Thanks J!m, I'll double-check the endplay and get an actual measurement with my dial indicator, I was just guesstimating the forementioned figure. Iwas looking at the PLH009 Drive flanges last night, I guess I'll get a pair coming...

[JSalyer]

springs

Dan,
measuring the springs may or may not help, as they may have sagged some(though I think not, as tall as your front end is), the number is also printed on the spring, but is very hard to see with the spring in place, so might be worth pulling one. it is in light grey lettering.
I work at Grafenwohr, retired from Hohenfels.....
later,
jack

[TigerDan]

UPDATE:

I decided to torch one coil off of each front spring to see what would happen. It lowered the front end by maybe 1/2 inch, but 90% of the buzzing noise/vibration problem disappeared. On the basis of that I ordered a pair of OME 761 springs, which I felt were a good match to the rear 764s for my application and useage. I installed them on Sunday and the difference is like night and day! The Rover sits level now, the vibration is completely gone and the handling and steering is much more stable and normal, in fact it's now pleasant to drive, I don't have to fight it. With an alignment I think it'll be right back where it should be.

I don't know what the front springs that were in it were as I can find no markings on them at all. They measure .695 on the wire diameter (as opposed to about .640 on my new 761s) and about 18" free length (allowing for the missing coil). They also appear to be a progressive spring, having tighter, closer coils over about 1/3 of the spring. Probably would have given me adequate ride height with a diesel (and a massive winch bumper/winch) up front...

Also, I bought a couple of universal 3-wire O2 sensors for 25 bucks each and solved the CEL/code 45 problem. Still didn't pass smog though, have to replace the converters. I have new ones now, probably install them this weekend.

Another annoying problem I've been having was when I start it in the morning, it fires right up but after 10 seconds or so it would drop a cylinder and not cold idle. I would have to nurse it for a ways and it wouldn't run well till it was fully warmed up. If it died while cold, it was very hard to restart. No codes, but I replaced the plugs when I did the O2 sensors (right bank were sooty black...no surprise there, with a bad sensor on that side) and got no improvement.

But when I took the shock out on the driver's side to replace the spring, I disconnected the coil wire and MAF harness to get them out of the way. When I reconnected the coil wire later I noticed that the ignition noise suppression condensor was nasty, rusty and cruddy looking. Thinking it could be partially shorted internally I unplugged it. It now runs good and strong right from cold and will even cold idle...so I guess that had something to do with it!

So, onward and upward. Nice to be getting some of the bugs worked out. Be nicer still to get some decent milage out of it. It was 8-9 mpg on the first couple of tanks with a jump to almost 12 after I replaced the O2 sensors and plugs. With this ignition problem behind me, and when I get the new cats in I'd be really happy if it got 15. I suppose that might be a tad optimistic...