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Hi all, just got a 1989 Yamaha Venture Royal Trike and trying to get in going. Have a dead miss (no compression), have a parts bike with a good engine. Was wondering if anyone does engine swaps?

 

 

Not sure where you are with this?

 

If you haven't swapped it yet post the compression results and mileage...

 

Patch

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Not sure where you are with this?

 

If you haven't swapped it yet post the compression results and mileage...

 

Patch

 

The one on bike1,3 & 4 run 140-150 psi, #2 about 20-30 psi. a shot of oil brought 1,3 & 4 up to 165-170. #2 maybe up 5 psi. Not sure of mileage but speedo is about 10,000, sure that's not right

 

extra engine mileage about 40K. Compression on all cylinders are 140-150 shot of oil 185-190.

 

Engine on bike is running but hits only on 2-3 cylinders.

 

John Carman

832 514 9608

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The one on bike1,3 & 4 run 140-150 psi, #2 about 20-30 psi. a shot of oil brought 1,3 & 4 up to 165-170. #2 maybe up 5 psi. Not sure of mileage but speedo is about 10,000, sure that's not right

 

extra engine mileage about 40K. Compression on all cylinders are 140-150 shot of oil 185-190.

 

Engine on bike is running but hits only on 2-3 cylinders.

 

John Carman

832 514 9608

 

 

Well you can bring me the bike, ship the engine or, go here

https://www.venturerider.org/forum/showthread.php?137296-A-Case-for-Fogging&highlight=case+fogging

 

There is obviously more that one issue here in play. I'll mull it over for a bit and come up with a troubleshooting plan if you are up for that.

 

Patch

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Before going all in for an engine swap I'd take a look in the low cylinder with a borescope. The problem could possibly be in the head with valve issues. Take off the valve cover and look for a stuck valve or broken valve spring. Bad engines and valve issues are both pretty rare in these engines so I'd make sure what is going on. If it's a piston or ring problem with that low compression it should be smoking pretty bad and have some serious blow by pressure coming from the crank case.

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For : John Carman/Jcfuzzzyface47

29/12/19

 

Interesting problem, so, requires some assumptions be drawn.

 

With Mileage and history not known; I would be curious to know witch control box is on the bike?

 

The 30 psi tells us that the piston is displacing and likely not holed. If for example you were reading between 50 & 60 psi there would be a fair chance for some promising gains.

 

Looking for connections between the timing in sequence such as 2&3 it is a safe bet that you have a failed pickup circuit. That is an easy fix and you just happen to have spares;)

 

Still we need to follow procedures to prove or disprove each potential!

I can’t say that changing the engine instead of repairing what’s in the bike is the better choice, yet; that is!

On one of my projects I brought a 4 cyl. From 45 above 150 psi using the fogging post we have tho, it was with the use of harsher chems than expressed in the post!

 

Where to start: 1st house power needs to be reliable (battier V.) I use a spare car unit with cables.

Measure voltage at the coils and log it, key set & run to on.

2nd measure resistance at the pickups, log it.

3rd using a spark gap tester determine each arch jump, log it.

4, remove picture each plug numbered by which jug they come from post them.

5, spin the engine no plugs and note if there is any slowing during the rotations. Does one stroke seem to slow the spin? Then look and listen to the engine thru each carb, (use protective eyewear) is there any pressure or spitting up thru the carbs?

Report back with results

Did I mention to disconnect the fuel pump and drain each carb bowl into a white container???

 

6, drop the pipes, one way or the other they’ll need to be so we can use this now for checking exhaust carbon buildup and if need be cleaning.

After pipes are off repeat the spinning of the engine cupping your hand over the exhaust ports; any vacuum pressure felt there is a fault!

7, remove the carbs, either way they need attention are worth quick cash assuming you have another set with the replacement?

8, spin it again now coupling your and over the intake pipes one at a time, it will surprise you but shouldn’t suck your hand off on these engine at these pressures ;)

Now do it this way, starting at 2 then 4 3&1 when you do 2 cover both intake and exhaust ports, yes you will need an assistant to push your buttons, preferably one that won’t distract you as she leans over;)

 

Report back your findings and we’ll see what the guys think.

So some are thinking “leak down test” yes but in any case the above will also prove just as or more effective and, it all needs doing in any case.

 

Patch

actually as many will attest to here my English is like the worst of the troubleshooting :)

 

---End Quote---

The one on bike1,3 & 4 run 140-150 psi, #2 about 20-30 psi. a shot of oil brought 1,3 & 4 up to 165-170. #2 maybe up 5 psi.

Not sure of mileage but speedo is about 10,000, sure that's not right

 

extra engine mileage about 40K. Compression on all cylinders are 140-150 shot of oil 185-190.

 

Engine on bike is running but hits only on 2-3 cylinders.

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Before going all in for an engine swap I'd take a look in the low cylinder with a borescope. The problem could possibly be in the head with valve issues. Take off the valve cover and look for a stuck valve or broken valve spring. Bad engines and valve issues are both pretty rare in these engines so I'd make sure what is going on. If it's a piston or ring problem with that low compression it should be smoking pretty bad and have some serious blow by pressure coming from the crank case.

 

 

Well Mr. Dawson I'm with you on the bucket but did you overlook somethin? hmm ;)

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Well Mr. Dawson I'm with you on the bucket but did you overlook somethin? hmm ;)

Nope. I don't know the wrenching experience of the OP so start with basics to get the brain moving in the right direction for troubleshooting. 1st step is never assume anything and get the head around the problem and consider all possible causes starting with the most likely and/or easiest to test moving toward a solution. There are multiple possible explanations but seeing in the cylinder and head will give insight for base line troubleshooting.

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Nope. I don't know the wrenching experience of the OP so start with basics to get the brain moving in the right direction for troubleshooting. 1st step is never assume anything and get the head around the problem and consider all possible causes starting with the most likely and/or easiest to test moving toward a solution. There are multiple possible explanations but seeing in the cylinder and head will give insight for base line troubleshooting.

 

 

Yes Mr. Dawson I see your point and, knew it when I wrote the schedule!

Allow me to pivot on your point without pointing finger to you specially, but rather seizing the opportunity!

 

So let me expose a thought I have been keeping to myself for a while.

As we know I enjoyed troubleshooting with Bongo, true we came at it from say sometimes apposing angles but neither one of us didn’t pick-up from where the other left off and, we hung in there till and for as long as the OP was willing.

Bongo is playing and likely lending a hand to members when needed in his new club so, it is up to this surviving membership to step up and fill in the how too blanks.

There is nothing I scheduled that we all haven’t witnessed, read and explained many times before.

Do I know if the OP has an ignition gap tester, no, and not likely; do I know you guys can walk him through it, post where and for how much he can find one, absolutely!

When OP begins looking for the pickup connection I have zero doubt that prairiehammer & video arizona and others will post clear pics, and instructions right down to driver size!

 

How many people has this club helped polish their skills and enjoy their ownership and membership then to stay on afterwards to continue in what makes this club different from the rest of the net B.S.?!

Time to stir the coals boys.

 

Patch

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Yes Mr. Dawson I see your point and, knew it when I wrote the schedule!

Allow me to pivot on your point without pointing finger to you specially, but rather seizing the opportunity!

 

So let me expose a thought I have been keeping to myself for a while.

As we know I enjoyed troubleshooting with Bongo, true we came at it from say sometimes apposing angles but neither one of us didn’t pick-up from where the other left off and, we hung in there till and for as long as the OP was willing.

Bongo is playing and likely lending a hand to members when needed in his new club so, it is up to this surviving membership to step up and fill in the how too blanks.

There is nothing I scheduled that we all haven’t witnessed, read and explained many times before.

Do I know if the OP has an ignition gap tester, no, and not likely; do I know you guys can walk him through it, post where and for how much he can find one, absolutely!

When OP begins looking for the pickup connection I have zero doubt that prairiehammer & video arizona and others will post clear pics, and instructions right down to driver size!

 

How many people has this club helped polish their skills and enjoy their ownership and membership then to stay on afterwards to continue in what makes this club different from the rest of the net B.S.?!

Time to stir the coals boys.

 

Patch

I prefer to use the KISS method of troubleshooting (Keep It Simple Stupid method) before diving deep. Seeing the jug and head will reveal if there is catastrophic damage or not causing compression loss. Knowing the dependability of these V4s I wouldn't overhaul one with cylinder damage. The cost of parts and labor of overhaul vs the cost of a low mileage used isn't worth it to me. If there is internal damage I don't waste my time further checking the bad one, time is short therefore expensive to me. I hope my engine building days are behind me, I just don't enjoy it anymore. Back to the KISS method I will admit to learning that the hard way on occasion. There was a time I'd tear down a bad engine just to see why it went, I'm just not that curious anymore unless it just did something very weird. :sign back to topic::sign13:

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Believe I'd put the bad cylinder at top dead center and install the compression tester hose ( assuming it has quick disconnect) and then hook up air compressor and see if the valves are leaking. You should be able to feel the air coming out the carb or the exhaust.

Might need to adjust valves if the shims make it to tight , you can check the clearance with feeler gauges see the service manual for how. Or You might have bent valve which I had on an 88 Royale.

You can replace the head in the bike.

Good Luck

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It's uncommon for engine failures, these things are pretty bulletproof, and also pretty darn heavy if you have to swap one out. Also depending on your comfort level it might make more sense to swap out a head than a whole engine if it comes to that. I like the borescope idea, a squirt of oil bringing up the compression suggest some possible ring/cyl wear which should be visible if it lacks compression that much. I'll assume that 10k is probably 110k mi depending on how other wear items on the bike look. 110k is a lot of miles on a bike that may not have been looked after properly. I hope you get it sorted, luckily parts are readily available and the wrenching is fairly straight forward. Mine has 75k and runs like a champ. We see a lot of Vmax and Venture with over 100k and still going strong.

 

Welcome!!

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Appreciate all the tips but I'm 72 and not looking to do any major engine work. Simple things I can do ans enjoy them but the COPD has stopped all my major work. About ready to just give up. Got 2 parts bikes just need someone to swap the parts around. Willing to pay a fair price for work done.71284713_2486149941464135_5828425016156356608_n[1].jpg

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