Subject: VW Type 3 shakes and shudders during cruise
Volkswagen4me
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posted on August 14th, 2017 at 05:21 PM
VW Type 3 shakes and shudders during cruise
Hi all,
So something odd happened the other weekend with my VW Type 3, and it'd be great if anyone has some advice:
The other weekend I took my 1970 VW Type 3 fastback for a cruise down the coast, driving for what was supposedly a 2hr trip one-way, and around 2hrs
back. About one and a half hours into the trip, the car started to 'shudder' (the whole car vibrated/shook and began slowing down). Keep in mind
this was after driving for a while at highway speeds of 80 to 110km/hr. Pressing the clutch pedal in, the shuddering stopped, and the engine revved
freely as normal. But when I released the clutch pedal and put my foot on the gas the 'shudder' kept happening. Needless to say, I pulled over and
turned off the engine. I couldn't see anything obviously wrong with the motor from a glance over. After 10 mins of waiting, I started the car up and
it ran fine for another 15 mins until it did the same thing.
Travelling back, I experienced it once more after driving the car up a fairly steep, curving mountain road 15 mins into the trip, and once more on the
highway after travelling for just under 2 hrs.
Any ideas what could be happening? I've never experienced this before, and most of my drives from home are usually only up to an hour away. Could
something be heating up? Or maybe there is an issue with the clutch slipping?
If anyone has any thoughts, suggestions or similar experiences, it'd be great to hear from you!
Also, thanks for those who endured reading this long post!
Cheers
'70 VW Type 3 Fastback
vw54
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posted on August 14th, 2017 at 07:53 PM
Could be your engine mounts loose or gone beyond repair
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posted on August 14th, 2017 at 08:07 PM
Have you checked your points gap?I had similar symptoms to those you describe. I filed and gaped the points and it solved the issue. Worth a try.
ACE76
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posted on August 15th, 2017 at 12:40 PM
If it shakes AND loses power suddenly, one of the carb. linkages could have fallen off: the small rods to lower outside of each carb. (but this won't
get better with a rest!)... idling is unaffected if one rod falls off.
Otherwise:
Fuel blockage / fuel starvation (poss. to one carb.) This can get worse as trip time and/or speed increases. CURE: Check all jets (esp. main);
carb. fuel levels, needle+seats, fuel filter/s, fuel pump, and accelerator pumps.
Or possibly a bad/failing condenser (capacitor). It can play up causing mis-firing at higher rev's - and behave as normal at idle. OR it can play
up when warm/hot, and behave OK when cold: so can suddenly mis-fire during a trip. CURE: Check condenser and/or replace if at all "suspect". Check
for VERY SMALL spark only at the points when engine off, ignition on, and engine hot. If the spark is "large", the condenser is failing.
Or clutch cable conduit not adjusted properly?
ACE 30 & ACE 40 oil: specially formulated for your Air Cooled Engine...
Delivery free Outer Eastern Melb. & Dandenong Ranges.
from$19 for 2.5L (spot-on for 1 fill, re-use bottle to measure), or $29 for 5L (2 fills)
wombatventures
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posted on August 16th, 2017 at 04:24 PM
Following on from ACE76s comment. I had some slightly more serious but similar issues with the Notch.
Check your fuel filter - the in line one. While its off, empty your tank into a container.
Where the fuel line comes out from the bottom of the tank, undo the nut and you'll find a filter in the tank.
While its out pour some clean fuel into the tank and let it flush out the outlet hole.
I was amazed how much crap came out and how much was blocking the in tank filter.
And this filter isn't mentioned in the workshop manuals.
Even if this isn't the only problem, it's worth doing for piece of mind.
Happy hunting.
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posted on August 16th, 2017 at 06:12 PM
Yes wombatventures, good points; forgot about the filter in the tank.
It's possible for water (+dirt/rust) to collect in the lower areas of fuel line too... could do initial check by removing wheel (with car SECURELY on
AXLE STAND), disconnecting hose under LHS rear (above axle, near clutch cable), and draining some petrol at that point, checking for free flow as well
as letting any water/rust out (may be easier to get at, than draining from bottom of tank).
This length of hose is often neglected, may need some spare hose/s to replace it. It should have a joining section of steel in it (or maybe a
filter): the forward section is 8mm, the rear 6 (or 5.5mm) I.D. When finished make sure the hose isn't dangling on the axle or CV/boot (can tie up
with a few cable ties, or use one inside engine compartment to hold it in place; leave some slack in it!). Fuel pouring out the hose while you are
replacing the line/s can be blocked with a round/tapered object such as a large pencil or centrepunch of the right size -- check size on the new
hose/s first! If you can't do these checks, most garages should be able to.
[Actually ALL the fuel hoses should be replaced if old. Small hose clamps should be used on each join (at least) from the fuel pump onward.]
ACE 30 & ACE 40 oil: specially formulated for your Air Cooled Engine...
Delivery free Outer Eastern Melb. & Dandenong Ranges.
from$19 for 2.5L (spot-on for 1 fill, re-use bottle to measure), or $29 for 5L (2 fills)
wombatventures
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posted on August 17th, 2017 at 07:34 AM
I was dead set surprised when talking to the older Guru's (Keith Poole and Alf) at Dub's by the River last Year. (Sad when you turn up to the VW get
together that you've organised in your folks Falcon because your VW has refused to run right!)
Their first diagnosis was not enough fuel, - "have you checked the filter?" Answer - "yep it was clear, changed it anyway."
"What about the one in the tank?"
HUH! Who knew!
Even guys who'd had a dozen VW's were surprised. Is it only in the Type 3?
I've never checked in the Kombi or the Super. Will when I work on them though.
It's easy forgotten or in my case not even known about.
When I gave the carbs a service after, I found a small bit of crap that had lodged in the needle and seat in one carb. Probably from pulling the fuel
pump off to change it.
A clean and or replace where needed all the way through the fuel system is never a bad thing. Especially with what these new fuels do to old lines
etc.
Hope you find the fault easily.