33 rear shockers??

[ericthered]

hi all,

while working on my 33 i noticed that it seems a bit bouncy on the back end , so i took a damper/shocker off expecting it to be knackered but it seems fine?
good constant resistance all the way.

everything on the suspension is good too?

is the 33 a little bouncy? if so when i go for an MOT i think i will have a hard job convincing the tester that its normal!

best wishes,
Eric.

[spunkymonkey]

Eric,

having just sorted this with mine, I can say that a decent set will give the normal "one bounce" if you push down and release. My old ones were giving 5 or 6 bounces but, comparing to the replacements, there wasn't a lot of difference in the resistance.

Finding replacements is a problem - I ended up getting a pair of used from Danny in Holland and chosing the best two of the four that gave me. NAPA in the US do some that John's fittes successfully, but they're a little longer than spec, and have to be fitted "upside-down" with the dust covers pointing upwards. If you go for them you're better off removing the dust covers altogether. The covers aren't an MOT item, but having them upside-down creates a very nice crud-catcher to fill with mud / water / whatever!

The NAPA parts are made by Monroe, and their tech helpline confirmed that the Monroe part number is Monroe 32206.

Alternatively, if there are no leaks and there's steady resistance (ie: the internal seals are ok) then it's entirely possible to drill and tap an existing unit, refill it with slightly thicker oil (15w/40 multigrade would be about right) and fit a threaded plug to seal. This isn't as "nasty" as it sounds. In the good old days a lot of shocks were refillable - in fact, the 33's front struts still are. The only reason for not making them refillable nowadays is the disposable society we live in!

I'll be doing this with my spare two when I get time & will post another pic series when I do

[ericthered]

hi Spunky,

thanks for the info, i have rebuilt shockers before (ones you can take to bits) so i think i will check carefully for leaks and if all is well have a go at the drill, fill and tap trick

15/40 seems a bit thick but once its got a plug in them i guess i can change to thinner if need be, with thick oil they should be very sporty! LOL

at the moment i get 5 or 6 bounces like you had :(so will have to do something.

will probably do it next week sometime and will let you know how i get on.

best wishes,
Eric.

[spunkymonkey]

Had a look at one of mine after posting that, and it seems "safe" to drill about 1/2 inch down from the end where the rod enters - so it's still just hidden by the dust cover when they're fully extended.

As a "tester" I used a 2.5mm drill, the 15w/40 I'd suggested and sealed with a brass taper plug hammered in. Filling was a bit messy with that size hole - best way seemed to be a plastic litre bottle with the top cut off, put the shock in it, fill bottle with oil and pump till no bubbles come out

Seems to have worked pretty well and a definite improvement on the resistance.

[ericthered]

hi Spunky,

did the shockers yesterday and now they are fine , i refilled them with correct "anti foam" hydraulic shocker oil as i had some in the garage, also rather than putting a plug in the drilled holes i tapped them out with an 4mm tap and fitted screws with a fiber washer.
the whole job only took a couple of hours! i did not even jack the car up, just crawled under to remove and refit.

thanks for the suggestion on drilling the holes, works a treat and recommended!!! no more bouncy rear end! LOL best wishes,
Eric.

[spunkymonkey]

Eric, glad it worked. Will be doing my spare pair "properly" sometime - a 4mm hole sounds like a good plan for ease of filling. I'm guessing that shock oil is still available from bike shops for forks. Might even clean the outsides and paint them!

[littlebelter]

Resucitating this thread from earlier this year.

My 33 rear shockers are in the 4 or 5 bounces category and I am "having a go" at them.

ericthered mentioned anti-foam hydraulic shocker oil. When I phone my local motorshop I get a dumb silence when I ask for this. They have ordinary hydraulic oil.

I'm a bit reluctant to put in 15/40 lube oil as it might react with seals or whatever lurks within a shocker.

Local motorcycle shop sells fork oil in varying grades. I think I will perhaps go for a heavyish grade of this.

I looked in the manuals to see what oil is used in the front dampers but of course they don't divulge this!

Those of you who have done this job before . . . does the refilling last a reasonable time ? or does the the new oil quickly vanish to wherever the original oil went to?

Regards,

Pete.

[daf44]

hi pete.
i have not done daf shocks like thisbut have done it to plenty of others.

the only way to find how long it will last is to try it.
if the oil seeped out gradually over thirty odd years but the seals are still intact then refilling like this could well outlast the car.

if the oil seals have gone, then it will probably not last to the mot centre.

the only way to find out is to try it. it is easy enough to do so has got to be worth trying.

let us know.

paul44

[starider]

Hi,I am quite old and my memory is not as good as it once was,but I seem to remember that 33 rear shocks are the same as the Mini.I am not sure whether front or rear-- or not at all![after all the brakes are Mini].I will contact a friend who has worked in Partco for 43 years!!! and see if he can remember/have access to old catalogues. starider.

[littlebelter]

I measured the ones off the Van and they are 325mm open and 250mm closed. This is the maximum overall length.

A pair of 31 rear shocks just went on ebay for a fiver but they have an eye at each end.

Seem to vaguely remember someone mentioning mini shockers before but can't remember what (if anything) came of it.

Cheers,

Pete.

[ericthered]

Hi Pete,

Paul44 is right, if your seals are well gone they wont last long!

my seals seem to be ok and the shockers did have plenty of oil in them when i drained them but it must of been pretty poor being almost 40 years old as once refilled they are spot on! ;D

i would just use fork oil, i only used this special "anti foam" stuff cos i had it, i think all damper oil is "anti foam", just that when i got this stuff they charged me good money (is there any such thing as bad money? LOL), for it as it was for a very expensive car and they played on it being special "anti foam".

its not hard to do so just give it a go.

Best wishes,
Eric.

[starider]

Hi still trying to find out if shocks are same as the Mini!! starider.

[littlebelter]

Hi John.

These look like the ones you have to fit upside-down.

They may do the job if you can't get anything else but (as "spunkymonkey has already observed) I reckon the cover would be a liability.

The other question is would they work properly upside-down?
I have taken one off the van so far and topped it up - not yet refitted. When you turn it upside down there is much less resistance on the compression stroke than when it is the correct way up.

Do you know the dimensions of those in your illustration?
I measured the ones off the Van and they are 325mm open and 250mm closed. This is the maximum overall length. The length of the Cover part is about 85mm and the length of the business part is about 140mm.

Regards,

Pete Hayselden.

[spunkymonkey]

Pete, when I was looking for mine, I contacted Monroe with the details of the NAPA part that John has used successfully in the past. Thery're actually a little longer than the original parts but we know they work from John's experience. The email and their reply is summarised below. So, they confirmed the part number but didn't give any advice on the upside-down fitting:


Message: I need rear shocks for my Daf 33, which is no longer listed by
anyone. A contact in the US has informed me that NAPA offer one that fits,
under their reference 94037 and they believe it's made by Monroe.

Unfortunately, I'm in the UK and NAPA won't deal with us over here so I
hope you can help with your reference for a suitable unit.

The original (that I'm trying to match) has a closed length of 7" from the
centre of the eye to the step of the stem. Top fitting is LS29 and bottom
fitting is S1 (S4 would be ok).

The NAPA part is specified as below and has been confirmed to fit with a
little modification, although it has to be installed "upside down" which
concerns me a little with a dust guard fitted:


Shock - NAPA Response - Front

Front

Part: RR 94037
Product Line: NAPA Response

Lower Mount : Loop Type 12MM x 1 1/4"
Shock Compressed Length : 8.375"
Shock Dust Shield : Yes
Shock Extended Length : 12.500"
Shock Parts Pack Part # : P1137
Shock Travel Length : 4.125"
Upper Mount : Stem 3/8" x 16


Their response:

Joe,
This changes to a Monroe 32206.
Monroe Team Member,