Wacker pedestrian roller problem

Discuss pavers, rollers, mills and other paving equipment here
User avatar

Topic author
mambo
Posts: 172
Joined: Sat Apr 07, 2012 10:51 pm
Real name: Brian
Location: Suffolk
Has thanked: 7 times
Been thanked: 27 times

Wacker pedestrian roller problem

Post #1 by mambo » Fri Aug 30, 2019 11:06 am

So I’ve got a roller I’ve not used for about 5 years
It’s beed stood under a tarp just as it was last used.

I dragged it out today to use and can’t get it to start, it turns over freely when decompression is engaged but doesn’t fire up when the lever drops into the start position

I tried a shot of easy start in the primer port on top of the cylinder head first, which produced 1 turn and a puff of white smoke. Tried a few more times and not getting anywhere so cracked off the high pressure fuel line at the injector. No fuel comes out while cranking, but if I pull the return pipe on the low pressure side of the pump fuel pours out.



If I crank it over with the return pipe off, the stream of fuel that’s coming out glugs like the pump is operating

Any help would be much appreciated

Image
Image
Image
Image

User avatar

FOWLER MAN
Posts: 2219
Joined: Wed Dec 09, 2009 11:28 pm
Real name: fred evans
Has thanked: 1082 times
Been thanked: 953 times
Flag: Wales

Re: Wacker pedestrian roller problem

Post #2 by FOWLER MAN » Fri Aug 30, 2019 5:45 pm

Hi,
Probably an injector pump problem.
Sounds to me the delivery valve is stuck. Take off the injector pipe then screw out the fitting that the pipe was attatched to.
Take care as there is a spring and plunger behind the fitting. That is the delivery valve plunger and it may be stuck, if so carefully use a point nose plyers and you should be able to free it and that should sort it out. :thumbup:
If however this valve is free take off the fuel feed and undo the three nuts holding the pump. Pull out the pump, (you may have to move the throttle lever as it comes out).
You will see the rack with the ball joint attatchet, this should slide freely from side to side. Be careful that the ball engages in its socket when refitting the pump and replace all shims as found.
On the inner end of the pump you will find a plunger with a roller attatched. Make sure it is not stuck in.
You should be able to push it in against the spring pressure which will then return it.
Let us know how you get on.

Fred

User avatar

Topic author
mambo
Posts: 172
Joined: Sat Apr 07, 2012 10:51 pm
Real name: Brian
Location: Suffolk
Has thanked: 7 times
Been thanked: 27 times

Re: Wacker pedestrian roller problem

Post #3 by mambo » Fri Aug 30, 2019 9:25 pm

Ok thanks Fred sounds like it may be an easy fix but I had to go hire a wacker for the job I needed it for now. I’ll have a look at it when I get a chance, may be a week or two but I’ll definitely report back
And thanks for the very comprehensive reply it will be very helpful and much appreciated

Thanks Brian

User avatar

Topic author
mambo
Posts: 172
Joined: Sat Apr 07, 2012 10:51 pm
Real name: Brian
Location: Suffolk
Has thanked: 7 times
Been thanked: 27 times

Re: Wacker pedestrian roller problem

Post #4 by mambo » Sun Sep 01, 2019 12:33 pm

I’ve takes the whole pump out as I couldn’t get the “fitting” loose. I’ve had it in the vice and applied mild torque to the fitting with a 19mm spanner but no joy do I just need to apply more effort? I’m concerned I may break something, you know. It’s not a left hand thread is it?


Image


The little throttle linkage with the ball on was a little stiff but I’ve given it a light shot of 3in1 and it slides freely now



Image


The little roller at the end spins freely and the plunger it’s attached to does move if I push it against something solid, I’m guessing it’s a tight spring and is designed to have a fair bit of resistance


Image

User avatar

Topic author
mambo
Posts: 172
Joined: Sat Apr 07, 2012 10:51 pm
Real name: Brian
Location: Suffolk
Has thanked: 7 times
Been thanked: 27 times

Re: Wacker pedestrian roller problem

Post #5 by mambo » Sun Sep 01, 2019 12:57 pm

I’ve got the fitting out, it took considerable effort with a 2ft breaker bar though.

This is what was inside. All looks good to me, I’m guessing that’s where the o-ring belongs as it was halfway down the thread when I got it out
Image

Does the pump need to be stripped any further? If so what’s the sequence?

User avatar

Topic author
mambo
Posts: 172
Joined: Sat Apr 07, 2012 10:51 pm
Real name: Brian
Location: Suffolk
Has thanked: 7 times
Been thanked: 27 times

Re: Wacker pedestrian roller problem

Post #6 by mambo » Sun Sep 01, 2019 1:05 pm

I’ve removed the circlip and there is a pin beneath, can’t see any way of removing it


Image


Jeremy Rowland
Moderator
Posts: 7444
Joined: Sun Aug 05, 2007 8:36 pm
Real name: Jeremy Rowland
Has thanked: 1293 times
Been thanked: 1142 times

Re: Wacker pedestrian roller problem

Post #7 by Jeremy Rowland » Sun Sep 01, 2019 4:35 pm

Brian the little part with four flutes on it and the spring are the delivery valve components; the rest of the guts of the thing I'm guessing would be a plunger and a rack, part of the rack is the little part with the ball on the end, that looks like it is free. Perhaps Fred may have some words of knowledge and wisdom to guide you here.

Jeremy

User avatar

FOWLER MAN
Posts: 2219
Joined: Wed Dec 09, 2009 11:28 pm
Real name: fred evans
Has thanked: 1082 times
Been thanked: 953 times
Flag: Wales

Re: Wacker pedestrian roller problem

Post #8 by FOWLER MAN » Sun Sep 01, 2019 7:19 pm

Hi Brian,
There's no point in stripping the pump any further as there is nothing more you can do yourself.

If everything is free, (and yes the spring behind the plunger is strong), replace the circlip and put the pump back in.
At this stage leave the delivery valve plunger and spring out. Just screw in the fitting witout it, hand tight will do. Then connect the fuel supply/return and make sure it is charged with fuel, then open the throttle.

You will then probably have fuel running from the injector pipe connection on the pump. If not turn the engine quietly and fuel should start to flow. Once the fuel is flowing from here there should be no problem. Replace the valve and springand tighten everrything.
Leave the injector pipe off at the injector end and turn over the engine till you get fuel through.

With any luck it will be fine.
Fred

User avatar

Topic author
mambo
Posts: 172
Joined: Sat Apr 07, 2012 10:51 pm
Real name: Brian
Location: Suffolk
Has thanked: 7 times
Been thanked: 27 times

Re: Wacker pedestrian roller problem

Post #9 by mambo » Sun Sep 01, 2019 7:32 pm

Ok thanks Fred I’ll get back on that next weekend :thumbup:

Thanks again for your help


Return to “Paving Equipment”

Who is online

Users browsing this forum: No registered users and 2 guests