1984 Interceptor in Vermont

how about timing?

 

I've checked the gap on the plugs and they are right on, and clean. I checked for spark, but everytime I think about it I wonder if the spark could have been bigger than what I saw. I have a friend coming tomorrow to give me a secong opinion on how big the spark should be. I also have no idea if they are firing in the right order, but as I never messed with the timing of the engine I would think they are.

 

I haven't checked the timing, but I haven't opened this motor "up", so I suspected that the timing should be in order.

 

i'm not at home right now to look at my bike, but there are two wires that go into each coil, one coil has a black with a white stripe wire and a blue wire connected. the other coil will have a black/white stripe wire and a yellow connected to it. if i recall correctly, the black/yellow combo feed the coil that supply the spark to the front cylinders. are the coils hooked up right?

 

I just got a compression tester that fits the tiny spark plug holes on the vf500f.
The results were:
(Dry Test) Front Right 50, Front Left 115, Rear Left 20, Rear Right 55
(Wet Test) Front Right 75, Front Left 100, Rear Left 93, Rear Right 100

I think I found out why the bike wont start.

A few people have told me that if an engine has been sitting a while, to add oil to the cylinders. The oil will raise the compression test results as they will seal the piston rings, but the numbers wont fall dramatically. This was from some guys that worked on 1960/70's car engines that had been sitting for years and years. I think I'll re prime the carbs and fuel line and give it a try in the AM, but I'm not very hopeful.

I have another engine that worked recently until the famed 1st gen issue occured and a valve dropped. I'm thinking about using the heads to the poor compression motor to the dropped valve motor. There's only a small ding in the top of the piston on that one, and I don't think it will affect compression in that cylinder too dramatically. Thoughts?

 

i'd say go for it. worse that will happen is you will still have two dead engines.

question regarding the dropped valves. is this issue due to random weak springs?

 

You've learned alot from this project, and that's great !!

Now you've also learned that any neglected VF 500 is a questionable investment of anyone's time and money, and mostly an excercise in frustration.

there are very good reasons why many of these old slappers are available cheap, cuz they can't be fixed unless you're willing to pour stupid money into it and have the luck to locate good, useable, low mileage parts.

 

squirrelman, I hear you do great work, I would of asked you if you'd do work on my carbs but I guess not.

 

So 25 years working on bikes and 35 years doing carbs don't mean shit to you ?? I've got tons of local work now, and your carbs, welcome on my workbench anytime, will not be MY problem if they don't come in but probably YOURS.

<<<<<>>>>>

Maybe it's time to start another "Squirrelman's a nasty, dirty old preverted loser-man , dick, & douchebag cuz he don't like gen 1s and isn't reluctant to say so," thread, and even worse, he's a self-described "Liberal," the sort who's responsible for America's problems, has been known to kiss certain rodents, and Johnny, you're the one who can get it done along with help from Ferro vecchio and others.

 

LOL, squirrel!

A Zen-like Koan - what is the difference between a basket-case from 1985 and one from 1995? Answer - a couple of hundred dollars and an ENORMOUS difference in frustration level!

And I feel qualified to speak on this because I own a 1984 VF750F. I wrench on that bike WAAAAAAY more than on my 2004 VFR. Why? Because it is a flawed machine with fairly crappy design and execution. Why do I bother? I am a flawed person with fairly crappy design and execution.

 

Hey jonny, I cleaned out my carbs as I thought that was the problem with my engine. I had never touched a carb in my life, but cleaning it was really simple with the help of the clymer manual (which is a bad manual). Cleaning a carb, at least on this bike, is very easy in my opinion, do it yourself. Also, you don't happen to go to UVM do you? I saw an 84 vf500f parked on campus on my way to the hospital on campus on Wed.

 

Always insightful you passive aggressive bastard.

 

I don't nthink thats was his thoughts squirrel. you rail anyone that wants to rebuild a gen 1 . JWB hears that you do good work then sees you rail a dude about the bike. honestly, I wouldn't send you anything to work on that all you do is badmouth it... so we all know that the 1st gen's had problems.........we get it go on with your life... besides you should love the fact that these bikes are comming out of the woodwork being a mechanic and all. i thry not to wish bad fortune on most people but think of the job security that you'll have

 

All of Squirrels opinions are correct....he just doesn't care how he comes across.

People need to know (when hoping into a first Gen) that there WILL be PROBLEMS....and Squirrel gets that across the fastest.

No one can deny that he's a bit of an ass.....but so are some others on here.

...and no one can deny that his dislike of the VF's are due to valid problems.

So lets all just relax and be cool.

 

It is a bit of a laundry list but these are the things to look for:

Troubleshooting Guide for Low Compression

1. Valves

- incorrect valve adjustment
- burned or bent valves
- incorrect valve timing
- broken valve spring

2. Cylinder Head

- leaking or damaged head gasket
- warped or cracked cylinder head

3. Cylinder and Piston

- worn cylinder or piston ring

 

+1, great tech tip!

 

If you hydro-lock a motor.....can you safely assume it has good compression?