Motor is still "stuck"

[Steve Minor]

I still can't seem to break free the piston from the "jug" on my 1977 400 restoration. I've been soaking the assembly in penetrating oil and giving it an occasional tap with a wooden dowel and hammer....I'm afraid of mushrooming the top of the piston..Any way to press it out? Or I'll gladly accept any suggestions!!!

[grandpaul]

It's time for the occaisional tap to become frequent whacks. You will most likely need a new piston & rings anyway (recommended). Just have to find that fine line between 'just right' and 'too hard'! (Too hard=bottom end overhaul, too)



GrandPaul,
Host of the Vintage Bikes forum at //www.delphi.com/oldbikes and the Triumph Bonnevilles Forum at //www.delphi.com/grandpaul

[grandpaul]

Steve wrote:
You've been very helpful in my effort to "unfreeze" my piston in my 1977 400 GS6 restoration project. If worse comes to worse, what can I expect to pay for a top and and bottom end rebuild?
Thanks, Steve

I replied:
Steve:
Hope you were able to pop your piston loose. Look at paying about $150-$200 for top end parts, about the same for bottom end (seals & gaskets mostly on bottom end) If you bend a con-rod, probably another $100. If you have to farm out the labor, look at a $500 budget (probably somewhat less if all done at once). I'm going to post your question & my answer back on the POG message board because it will surely generate some better leads for you and may help others, as well.
Keep 'em rolling!


GrandPaul,
Host of the Vintage Bikes forum at //www.delphi.com/oldbikes and the Triumph Bonnevilles Forum at //www.delphi.com/grandpaul

[Rocket]

Steve
Don't give up on the Liquid Wrench and time.  Keep spraying and tapping on the piston.  Will the jug come loose from the cases?  If it won't break free from the case, the con rod bearing is probably stuck also.  I worked on my 400 getting the piston unstuck for better than a week after it has set for 23 years.
Rocket

 

[grandpaul]

Rocket - can you give Mr. Steve an idea as to what you ended up with budget-wise? Also your resources would be nice (always best from someone who's 'been there')...


GrandPaul,
Host of the Vintage Bikes forum at //www.delphi.com/oldbikes and the Triumph Bonnevilles Forum at //www.delphi.com/grandpaul

[john durrill]

Steve,
If you have Yahoo or ICQ try and get me. Ill be on tonight. If we can talk real time I might be able to help. Their are some short cuts next to my name in the members list that give you my #'s on either of the chat programs
John D.

 

[Doug Wilford]

Steve;   Make sure you have your cylinder stud wells full of penetrant also. I cradle the cylinder in my arms so the wieght of the engine is hanging free.   Take the largest wooden handled mini sledge that you can use in one hand and smack away.  With the position you will be in, I don't think you are strong enough to bust the piston. Once it breaks loose from the cases, keep moving it up and down.   Like Rocket says it will come apart, eventually.


 

[Steve Minor]

Thanks for all the suggestions....I'm gonna' keep trying to "unstick" the piston from the jug with liquid wrench and hammer taps.... I'm sure though I'll damage the piston beyond re-use....The jug is free from the cases and I might be able to slip some sorta wedge or lever between the cases and the bottpm of the jug. I just fear I'll screw up the bottom end in the process....Wonder is a machine shop could "press" it out?

In the mean time.....take it out and get it dirty........

[Rocket]

Steve
You have a good chance of getting the piston unstuck since the jug is loose from the case.  What Doug suggested about holding the jug and tapping the piston should work.  I got mine apart, cleaned everything up and even reused the piston and rings with no problems.  My 400 was a real low mileage bike to start with and everything measured okay.
Rocket

 

[john durrill]

Steve ,
I use wood blocks to keep the cylinder off the block and give me some room .
you could use 2x 6's or plywood  slotted all depending on how much room their is between the block and the bottom of the cylinder sound like you almost have it licked.
John D.

 

[Mark Annan]

try to find some PB Blaster Penetrating Catalyst.  I got a spray can from Autozone.  It is a great penetrant oil.  It might help

Mark