Jensen heritage for the next generation

Servicing the Jensen FF

Dear Diary discusses servicing the Jensen FF chassis number 119/191

From the Handbook of Instructions for the FF (October 1969)

Maintenance Diagram

FF Maintenance Chart

Serviving Details

Approved Lubricants


Jacking the Front

The manual provides: “When jacking up the rear end precautions are necessary to avoid damage to the subframe. For this purpose it is recommended that a steel bar measuring 3 inches by 5/8 ths X 23 inches be placed between the jack pad and the sub frame in line with the front upper suspension link.”

It has also been suggested that a suitably sized piece of 2″ X 4″ will do the same job ( if your car isn’t so low that you can’t get it in)

Before I read this instruction in the manual I was told to just jack it on the front chassis cross tube. ( have to say that this is still the way I do it, contrary to the manual):

Jacking point used is the front body tube. As the FF engine is on a subframe, jacking on the subframe itself is likely to rip it away from the body?

When I put the car up on axle stands I jack it up closer to the sill (still on the large chassis tube) and then place the axle stands inboard (still on the chassis tube). I repeat for each side.

Jacking the Rear:

Place a piece of 2″X4″ wood under the rear chassis tube at the jacking point location


Engine oil sump. Showing drain plug.

Photo of spare oil filter bowel showing the drain plug underneath.

Rear diffential filler/level plug Rear differential drain plug

Photo showing front differential filler/level plug and drain plug at bottom. Use Castrol Hypoy

Photo showing grease nipple on front axel to be graesed every 12,000 miles

Fuel filter located underneath car at the front and on the offside rail, to the rear of engine sump.

Photo showing centre differential (transfer box). The number is 102/195. Note box drain plug at bottom right hand side. I am now using Castrol Dextron 3 instead off the originally recommended Castrol TQ. When I came to change the oil, there wasn’t any. It must have leaked out over the 12 years it was stored.

I ask the List the following question about servicing the Jensen FF:

“I will be recommissioning an Oct. 1969 FF very soon and I will need, amongst other things, all the normal service items. Given that time has moved on since the cars manufacture. Do people still use:
1. Castrol GTX for the engine oil or a part synthetic or what? And which one?
2. Castrol Hypoy L S. for the Rear Diff?
3. Castrol Hypoy for the front diff?
4. Castrol TQ for the Automatic transmission and centre diff. unit?
5. Champion J11Y spark plugs?
There must be better items and oils today. What do you recommend? Finally Electronic ignitions? Ideally those that fit inside the distributor. Which one? the Mopar electronic ignition kit ? All help gratefully received.”

The answers I received were:
1) Do not use fully synthetic oils as they are very scavenging and will remove all traces of lead from your valve seats very quickly. I go for quality (and expense)Penrite 15/60 semi synth in the engine in the Winter and in the Summer unless I intend to do very fast Continental motoring when I use Penrite 20/60 mineral. Rear diff gets Penrite 85/140 Limslip (must be limslip) Bog standard Castrol 90 hypoy in the front diff Any good Dexron 3 oil in the boxes – I have Castrol in the Mk 1 but in the FF I am trialling some Millermatic DM, but one that has been specially blended for me to resolve the heating problems.You are obviously draining your gearbox oil – best of luck you will have to take the pan off, I have a deeper sump off a minibus that holds more oil and has a sump plug. You can get finned ali ones from the states.

2) I recommend the K&N Oil filter what a beautiful thing that is Has a hex nut on the end of it and the oil comes out the same colour it goes in. Of course the filter is 11 dollars but when you buy two filters a year it pays for itself. I’ve figured out my Mobil1 K&N changes compared to Dino oil and have come up with Mobil 1 two oil changes a year dino 7 changes a year so 64 dollars a year for Mobil 1 or 133 dollars a year for dino juice.
3) That’s a very interesting cost comparison. I had changed the JH to 0/50 synthetic ,the effect was immediate and dramatic . Oil pressure was up with no lag time on start up and the engine seems to run a little quieter and cooler.I have no problem with the expense for the Baby ,but when it comes to the 2 daily drivers I had always thought that changing the oil and filter often (5000 K)to remove contaminates was the way to go I would pay 30.00 per oil/filter change X 3 changes ,(10,000 K, synthetic oil ) versus Dino juice ( I like that) at $15.00 per change X 6 times .That’s $90.00 no matter what I do! It would appear that for the extra value of the synthetic oil and less work I will switch everything to synthetic oil !!

4) I’ll answer this question If you will allow me. I strictly use Mobil 1 10W30 in my engines Mobile 1 90 weight Gear lube in the rear and I don’t believe in automatic transmissions unless your 16 or a woman. By the way my Oldsmobile that has ran Mobil1 since birth 10 years ago just passed 212,000 My Supercharged Stang has ran Mobil 1 and has 50K on it without any trouble.I’ve never had a problem with the full synthetic damaging my lead heads.

5) I strictly use KENDALL GT-1 20W-50W in all of my cars. This is the most purest oil out there on the planet. You can easily get from 250,000 up to 400,000 plus miles, if the oil is changed regularly.My 1985 Audi 5000CS Turbo was using one quart of oil every 700 miles. When I was told about this five years ago, I flushed the engine and started using Kendall. I went almost 4000 miles before I had to add a full quart of oil. It made a believer out of me. I now have 200,000 miles on the engine, and I have never even took off the valve cover. I will be changing oil in my GT this weekend and replacing it with Kendall.As far as spark plugs, I recommend the NGK Racing plugs for the hi-performance V-8’s. I use them in my 1982 Dodge 360cid, and it starts and runs great. I will go with them in my Interceptor, after I do an engine rebuild, hopefully this year.
6) I have used mobil 1 syn in several of my cars, changing oil every 10,000 miles. Many being purchased with 100k miles,,i ran em to 200k, with no problems. I remember Mobil 1 advertising oil changes every 20,000 miles when it first came out in the 70’s or 80’s. I think the manufacturers screamed,,so Mobil went went a different advertising angle,,that being better engine protection. So i went with the more expensive Mobil 1 syn, [vs standard oil] but changed the oil and filter every 10,000 miles.
7) PS: All the advice on oil seems more or less OK. I am a bit confused too. What I actually do is buy standard ordinary GTX, and change it as soon as it starts to go black. When I first get a car I perhaps only get 1000 miles out of the first lot. If it is really dirty, I might buy some cheap oil, run it up for 2 mins, drain, and refill a couple of times. I did this to 119/036, the rusty one on the web site. The Chrysler MOPAR mailing list (similar to the Jensen one, only Just Chryslers, mainly V8s). They have FAQ, and suggest that the V8 with regular 3000 mile changes can still have cross hatches on the bores when using ordinary oil. I would like to use Fully synthetic, but the seals all have to be perfect, as it tends to leak more.

8) These engines will often cavitate if you don’t prime the oil filter bowl during an oil filter changes.

When I did the last engine oil change I replaced the original sump plug with a magnetic one obtained from Cropredy Bridge Garage


Photo of the replacement silicon sparkplug leads from Customville. Fitted OK. I also ended up using some plastic ties to help hold No 1, 6 and 8 leads away from the exhaust manifold.

I was advised that Autolite 85 Spark plugs are very good, as are Blue Streak contact breaker points.


Photo of fuse box

Fuel pump

For my Mk1 FF this is 1/8 toe out


I asked the list about belt widths:

I have a 1969 MK 1 FF. Does anyone know the correct width or the best width for the alternator and power steering belts? I’ve got belts which are 10mm and 12.5mm.

Replys were:

1.They are actually 10.5mm ..


Alternator belt Dayco 15375 11A0950 -229

Alternator belt Chrysler 2806216 42095 910D

Power steering belt Dayco RD Gold 3798 —-329-17435 13A1105 – this belt has a 12.5mm width


12,000 miles: Inspect, repack if any signes of leakage.

36,000 miles Clean and repack


To repack the front wheel bearings:
1) Jack up the front of the car (one side at a time, or both sides and use jack-stands) and remove the wheels.
2) Remove the brake caliper attaching bolts. These may be secured with lock plates, in which case you carefully bend down the tabs, or with safety wire, which you simply snip and pull away. In either case, you MUST secure the bolts after you replace them, either with the lock plates (new ones, if you can get them) or with safety wire. The tightening torque for the caliper attaching bolts is 55 ft. lbs.
3) Support the caliper with a piece of wire so that its weight is not pulling on the hose.
4) Remove the hub cap, the split pin and the nut. The hub cap is simply a press fit into the hub. Judicious tapping and prying (prising) will remove it.
5) Slide the hub straight off the stub axle, being careful not to damage the grease seal on the inboard side.
6) Remove the outboard roller bearings and clean them. Unless you are replacing the seals, do not remove the inner bearings, but simply clean them in situ as well as you can. Now repack the bearings with wheel bearing grease. Many auto supply houses sell inexpensive devices for repacking these bearings. Buy and use one, or simply use your fingers (messy!).
7) Re-fit hub to stub axle and tighten the axle nut to 90 INCH lbs. (note well: that’s INCH, not foot) while rotating the hub. Back off nut to next hole/slot alignment and fit split pin. This should give the .002-.006 permissible end-play. Replace the hub cap.
8) Refit the brake caliper, tightening the bolts to 55 ft. lbs. and replacing the safety wire or lock plates.
9) Refit the road wheel, lower the jack and tighten the wheel nuts to 50 lb. ft. torque.
10) Raise the car again and check the wheel to make sure that there is no tightness or binding or excessive play. Lower the jack and you’re on your way.(David Crowne)


Photo showing right hand side rear grease nipple for rear bearing (same on the left hand side)

Inspect, clean and repack only if grease has emulsified or been contaminated through damaged inner or outer seals

1) The rear hub bearings are not to be re-packed. They are lubricated through Zerk fittings on the forward side of the rear axle housing, just inboard of the rotors. With the rear wheel removed, these grease fittings are easy to see and easy to reach. Eight or ten strokes with your hand-held grease gun every 4,000 miles will suffice. (David Crowne)

2)The workshop manul refers to filling the hub bearings with grease until it comes out of the vent hole on the oposite side. However, in practice, there arn’t any vent holes. Excess grease would probably force itself through the inner seal into the dif