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Timing Chain Replacement on 2002 XR80R

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So we tore into the XR80R
I cracked the tight nuts and bolts...
the boys removed them. I have the manual on a cd, which is now loaded on the all in one pc which is the garage manual depository..
The manual is easy peasy...
go to chapter 7icon1.png for cylinder removal...
it states:
step 1 remove seat see section 3-2
step 2 remove side cover see section 5_6
and so on until the engine is removed
F6B89DFA-6DAF-4F43-85BF-B2A424B41283_zps

the boys kept at it between the manual and me telling them to bag and tagicon1.png everything we got the motor on the bench and the top off

82024F9E-48B3-4F78-A5AF-22F54EF2A2D4_zps

As you can see one tappet adjuster is missing. The motor did not get overheated and seize as i thought. The seized sensation was the adjuster in between the chain and the gear. What I thought me breaking a seized pistion free was me actually snapping this little timing chain.


46E34171-8804-414B-B24D-236B92C1A5E4_zps


i have read some contradictory posts about replacing this timing chain...
split the case and its not necessary...
can someone with practical experience help here?
this is a 2002 xr80r..
thank you for reading
Fritz
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This new thread to refocus from piston to cam chain

replacement ought to better draw out those with first

hand knowledge/experience. Until they appear, I'll

post some inexperienced remarks.

First. The topic has likely been discussed in the past.

Use of the advanced search feature will bring out examples.

Reliance on your Spidey Sense will be required to distinguish

smoke from substance.

Pending receipt of current advice and/or discovery of past

discussion, here are some arm chair thoughts.

The left crank shaft seal behind the plate the stator and points

are mounted on can be removed. If the resulting opening is

large enough to permit the cam chain to be manipulated so

it can pass through without damage to the links from twisting

and if a new, tighter chain can be installed in the same manner,

then the job is possible.

A separate but related task is replacement of the crank mounted

CC gear. Chains and gears wear together and should be replaced

together. Getting the lower sprocket off and installing a new one

in correct relation/timing to the crank without damage may/may not

be a challenge in the space available.

Seal removal.

It is important to avoid damaging the bore in the case and the surface

of the shaft in order for the replacement seal to be oil tight after the repair.

There are pick tools for seal removal, they resemble HD versions

of the tools dentists use to clean/probe teeth.

The outer circumference of a seal often consists of a sheet metal

ring with an 'L' shaped cross section. This ring is coated with the

seal material to provide a tight (pushed/driven) fit in the case. The

inner diameter is a ring of the seal material (possibly with a circular)

coiled spring within) with one or more molded lips intended to contact

the crank shaft for sealing.

The seal wall between the ID and OD is thin to be pliable.

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So ,

 I get all COB about the "face spanner wrench"and do this thing,

 

EC0A4A4B-5F87-4198-AA03-50B5D102EAD6_zps

 

 

I have the proper tool to remove that rotor...

 

 

puller1.jpg

 

 

The next thing that gave me a little pause, was the timing plate.

The 2 Phillips head bolts at 9 O'Clock and 3 O'Clock, were fixed with loc-tite. Did not know that and snapped 3 of the Harbor Freight bit which came with the impact screw driver that I bought...  My gramps said do not buy cheap tools...but that a whole other tale.

 

 

 

 

I went back to HF with the broken tips in hand. showed em to the man and he gave me 3 more tips to try and break... I also bought one of those butane micro torches... 

that worked.. 

Those Philips budged after the 3rd whack.

 

 

If you read further up in this long winded thread,  it is apparent that I am extremely reluctant to crack the engine cases on these small motors...Think Grandpas watch I never got back just right... come on.. it closed!

 

 

So I keep thinking about the pop the seal trick thats "rumored" to work...again read above...

 

But I did buy the gaskets in case that doesnt work...

 

I axed good Brother Paul to come supervise me if I have to split the case.

 

I tried to find the seal but it was 5 days out Thursday night, no matter who I tried to get it from...I ordered from partzilla.. 3.79 and the ride.. the local stealership wanted 9.89

 

Paul calls this morning and says he is on his way...

My sons are over and we just finished big bacon breakfast...

 

We go get the wrenching lube, MGDx24 and 30xPBR

by the time we get back and put the lube away, Paul shows up on his road couch as Axl, my 9 year old, calls it.

 

 

we look at the  engine case and before I can pop my beer, Paul has taken the seal out.

 

 

 

&%$#@! piss and hell fire he beat me to it...

We both then proceed to squiggle that cam chain around the shaft through the bore.  The 12" hemostats have found another use.  between the two of us the chain came through and we did not have to crack open the case.  Engine case that is.

 

F2C47BAC-300F-4E43-BA3B-96D882ABE045_zps

 

All thats left is to put the cylinder, head and cam back... 

align the marks and button down... 

 

Thanks for reading and the kind words of advice.

I have found, and I am a newb..

 

You can get the crankshaft seal of and the cam chain around the crankshaft and through the bore.

 

This motor had less than 24 hours on it... and it shows... we took  a look at the CC gear and it was in great shape.

Not just my opinion but my friends too.

 

Piston rings are spaced accordingly and proper, and new gaskets and permatex sealant are ready.

Edited by fritzl65

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Hope you found all missing parts and got them extracted from the engine.

Just 'cause there is an oil passage in the swamp of the timing chain, where chain parts or parts of the tappet adjuster might went through.

 

Since you already stripped the top end, i would recommend parting the bottom end to clean it seriously.

 

The pics were taken from a 100s case, very similar to the 80s. Sorry for my bad english,

Alex

 

 

Durchlass.jpg

links.jpg

Sumpf.jpg

Sumpf1.jpg

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thanks for the advice Alexxxx

i have poured some diesel into the bottom end and cleaned out the block..

my compressor helped

i am now in the process of reassembly of the top half..

valve train appears to be timed

"O" of the cam gear is on top and  the "F" mark of the rotor/crank is at 12 oclock 

 

tappet carrier was torqued to 15 ft/lbs

now here is where i lose it...

there is a single cylinder head bolt which the manual states to;

"Install the cylinder head mounting bolt, but do not tighten".

This is from page 7-15 of the May 1999 issued Honda 1998-2003 Service Manual'

On page 7-16 torque specs for cam shaft holder assembly appear

cylinder head cover bolt torque spec is given

from this point forward until the page 7-18 where it is written to start the engine..no mention of tightening this bolt is made...

no torque spec which i can see

 

please post this spec if you know it

thanks for reading

Fritz

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there is a single cylinder head bolt which the manual states to;

"Install the cylinder head mounting bolt, but do not tighten".

This is from page 7-15 of the May 1999 issued Honda 1998-2003 Service Manual'

 

no torque spec which i can see

 

please post this spec if you know it

thanks for reading

Fritz

 

Hello Fritz.

They just forgot telling to tighten this bolt together with the camshaft holder nuts.

 

Since this bolt is a 6mm flange bolt with 10mm head, you have to tighten it with 12Nm torque shown on page 1-14 in the manual.

 

See pic,

 

torques.JPG

 

Alex

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