V4 Went Bang On The Way Home The Other Night....

Hi

New member and the first post is one looking for advice, which I appreciate is a bit cheeky but still I am desperate to get this sorted and back on the road. I have been lurking for the last 3 months since I bought the bike, and appreciate the wealth of information from this site.

Bought an 03 VFR 4 months ago, VTEC version registered late 04 with 36k on it FSH up to 28k with receipts for the rest. No mods to the engine which would cause this issue as far as I'm aware, although a scottoiler has been fitted and I haven't as of yet got round to exposing the vacuum tubing to have a look at the joint. Aside from that its just handling/aesthetics mods like touring screen, heated grips, slip ons and an ohlins. 

I had the valve check done on this 3 weeks ago by a big, popular and well established dealer with a relatively long wait list at times so I am confident that the work was carried out correctly and was going to carry out the rest of a service with a couple of mods like a power commander this weekend.

Riding home late last week in medium traffic, cruising at 70-80 with low rev's say 5-6k. See a low speed vehicle in front so prepare to got for the overtake by dropping it down to preprae to pull into the overtaking lane and accelerate. As I get on the power again having downshifted there is a momentary loss in power, followed by what I assume is an bang coming from the intake. It then rides terribly for about 15 seconds, I cant pull over at that time, so ease off the throttle, on the overrun it sounds terrible so clutch in and pull over. As I pull over engine settles down and idles but only on 3. There is also a fair amount of noise coming from the intake every fourth compression. Ease it home as Im 3 miles from the door and its midnight with work to go to. Get it home gradually nursing it and shortfiting below 5k. 

Dimsmantled it today, take off the airbox lid and there is a smell of petrol in the filter as though it has been flooded by it. There is also a lot of rubbish kicked out of the rear near side air funnel. In addition to this there is quite a bit of this mustard yellow looking fluid splashing about in the intake housing for the tube going to the crank case breather. Looking at http://www.vfrdiscus...r-fuel-economy/it seems to be the fuel pressure regulator. But would that explain the terrible running for 15-20 seconds as described? Is there the potential for any long term damage? Ideally I dont want to take the heads of unless I really have to. In terms of how it was running when I rode it home, on three cylinders with low power. Approaching lights on the clutch in the engine would almost cut out so I heald the throttle at around 2k revs to prevent a stall. Its also running very rich and the exhaust stinks of fuel

Call the workshop that did the valves... that is a major job and requires opening up the motor... and it was only 3 weeks ago...

Did it  blow a  spark  plug  out ?

Call the workshop that did the valves... that is a major job and requires opening up the motor... and it was only 3 weeks ago...

Im going in to speak with them tomorow. 

Did it  blow a  spark  plug  out ?

Ive not got that far yet, have new plugs on the way to go in. My plan was to do oil/plugs/filter myself then fit the power commander. There didnt seem to be a violent jolt when I was riding it, more a bang with lots of noise for 15-20 seconds as decribed but cant tell if that was metal on metal.

The FI light is not on by the way, I forgot to add that at first

First off welcome to VFRD and Sorry this is your first post!!!! 

You own one of the most Bullet Proof motors in history, one blowing up is an extremely rare occurrence.  As mentioned I would tend to look at the work recently performed as the main possibility.

Keep us updated.

BR

Wow, that's a bummer.  :sad:   While extremely rare, I do seem to recall where someone posted up that they had one that dropped a valve.  Since you have the airbox lid off, it would be interesting to have a look down the air intake stacks.   Shine a flashlight down and open the throttle plates - you can look directly at the intake valves and see if they look normal.  If the compression's gone in a cylinder, the dealer probably has a scope they can look in the cylinders with.   Best of luck with it. 

You could  have  bent  some  valves.

Go ahead  and  pull  the  plugs  first . And  post  some  pic's  please .

It could be a number of things but the one fact that sticks out to me is you had valve service don't recently, I would 100% have the timing re inspected.

I know of 3 friends bikes that had dealer valve inspection & each one had same type of failures which were caused because dealer mechanic had cam timing wrong. Due to the fact the cams have to be removed a number of times to do vtec valve service & the tensioner is removed it is easy for one cam to be a tooth out if major care isn't taken. One friends motor suffered major damage because the dealer installed a cam cap the wrong way round which blocked off oil ways.

It could be a number of things but the one fact that sticks out to me is you had valve service don't recently, I would 100% have the timing re inspected.
I know of 3 friends bikes that had dealer valve inspection & each one had same type of failures which were caused because dealer mechanic had cam timing wrong. Due to the fact the cams have to be removed a number of times to do vtec valve service & the tensioner is removed it is easy for one cam to be a tooth out if major care isn't taken. One friends motor suffered major damage because the dealer installed a cam cap the wrong way round which blocked off oil ways.

This makes me glad i havent had my 16k valve clearance done.

It could be a number of things but the one fact that sticks out to me is you had valve service don't recently, I would 100% have the timing re inspected.
I know of 3 friends bikes that had dealer valve inspection & each one had same type of failures which were caused because dealer mechanic had cam timing wrong. Due to the fact the cams have to be removed a number of times to do vtec valve service & the tensioner is removed it is easy for one cam to be a tooth out if major care isn't taken. One friends motor suffered major damage because the dealer installed a cam cap the wrong way round which blocked off oil ways.

This makes me glad i havent had my 16k valve clearance done.

We  don't  do  valve  checks  here  UNTIL  we  have  a  good  reason .

First off welcome to VFRD and Sorry this is your first post!!!! 

You own one of the most Bullet Proof motors in history, one blowing up is an extremely rare occurrence.  As mentioned I would tend to look at the work recently performed as the main possibility.

Keep us updated.

BR

Thanks for the welcome.

Ive seen the "other" thread with a problem similar to this, it was BO I think. Exact same symptoms turned out to be a dropped valve. One of the main reasons for going for this bike was the all round reliability meant I could use it as a commuter too. 

Wow, that's a bummer.  :sad:   While extremely rare, I do seem to recall where someone posted up that they had one that dropped a valve.  Since you have the airbox lid off, it would be interesting to have a look down the air intake stacks.   Shine a flashlight down and open the throttle plates - you can look directly at the intake valves and see if they look normal.  If the compression's gone in a cylinder, the dealer probably has a scope they can look in the cylinders with.   Best of luck with it. 

I'm going to pull the other funnel off either tomorrow, or Xmas Eve because I am off work. There is a lot of compression noise similar to a blown spark plug or running the engine without a spark plug. If I can get a helper to turn the back wheel I'll take a video on my phone

You could  have  bent  some  valves.

Go ahead  and  pull  the  plugs  first . And  post  some  pic's  please .

Havent got as far as the plugs, as mentioned above something I'll be doing tomorrow or Wednesday. Pics are attached of how far down I have got into the engine (not far!) But shows all the rubbish to come out of the throttle body

It could be a number of things but the one fact that sticks out to me is you had valve service don't recently, I would 100% have the timing re inspected.

I know of 3 friends bikes that had dealer valve inspection & each one had same type of failures which were caused because dealer mechanic had cam timing wrong. Due to the fact the cams have to be removed a number of times to do vtec valve service & the tensioner is removed it is easy for one cam to be a tooth out if major care isn't taken. One friends motor suffered major damage because the dealer installed a cam cap the wrong way round which blocked off oil ways.

Were they all VFRs? My plan is to strip it down myself to find the cause and then if the dealer it to blame I can go and have a chat in an attempt to resolve it.

It could be a number of things but the one fact that sticks out to me is you had valve service don't recently, I would 100% have the timing re inspected.
I know of 3 friends bikes that had dealer valve inspection & each one had same type of failures which were caused because dealer mechanic had cam timing wrong. Due to the fact the cams have to be removed a number of times to do vtec valve service & the tensioner is removed it is easy for one cam to be a tooth out if major care isn't taken. One friends motor suffered major damage because the dealer installed a cam cap the wrong way round which blocked off oil ways.

This makes me glad i havent had my 16k valve clearance done.

The most annoying thing to me is I spoke with the service department about bothering about a 36k check. Said I have heard of them going to 64k with no issues. Said that I could get a new engine for around £2-300 if it went bang so was tempted to run it until I had an issue. Then changed my mind and got it checked as the bike was new to me and didnt have a history of having it done. The check sheet I have states they were all to spec by the way.

It could be a number of things but the one fact that sticks out to me is you had valve service don't recently, I would 100% have the timing re inspected.
I know of 3 friends bikes that had dealer valve inspection & each one had same type of failures which were caused because dealer mechanic had cam timing wrong. Due to the fact the cams have to be removed a number of times to do vtec valve service & the tensioner is removed it is easy for one cam to be a tooth out if major care isn't taken. One friends motor suffered major damage because the dealer installed a cam cap the wrong way round which blocked off oil ways.

This makes me glad i havent had my 16k valve clearance done.

We  don't  do  valve  checks  here  UNTIL  we  have  a  good  reason .

How do you know if they are within spec unless you get them checked? Sounds more as though you are waiting for the problem to occur then remedy it rather than a bit of proactive maintentance and servicing

Pics are of the airbox mess, apologies for the quality

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You  have  blown  a piston  my  friend   SORRY  !!

Call the  shop  that  did  the  work  and  tell  them  you  drop a valve  and  your   motor   is  trashed .  

Surely the shop is liable for this damage,I wouldn't touch it,put it on a trailer and leave it with them to sort,you have legal rights here IMO.

Let's  hope  .   ^^^

Tight valves are too quiet and can have trouble starting the engine from cold, lose valves are noisy so youd notice. I think thats right?

Mm what a bad do you're having! I dont know what rights you have in your country, but in the UK youd defo have the law on your side IMO.

All the best with it mate!

Don't touch anything on that engine!  Don't even inspect, poke, move, adjust or start the engine. If you do whatever the dealer finds wrong with the engine will fall on you.  Any warrantee to the recent service work will be null & voided.    R3~ 

+1  forget  about  pulling  the   plugs.

Think of it as a crime scene.  Any poking around you do will contaminate the evidence.

Darn  lucky  it  did  not  lockup  the  motor. Could  have  been catastrophic .

SuperBeef you're getting a lot of amateur speculation here  with no actual troubleshooting procedure. A simple compression check will tell you if the piston or valve have been damaged. That is the very first step.

Excuse my lack of knowledge here.

How can a coil blow a plug out?

I thought they just stopped sparking, n just didnt run on that cylinder when a coil went?

Excuse my lack of knowledge here.

How can a coil blow a plug out?

I thought they just stopped sparking, n just didnt run on that cylinder when a coil went?

+1.....

Coil dies, you get no spark, but I don't think you get a big plug spitting "asplosion" at the then dead cylinder..... :huh:

Sorry for the lack of updates, working over the holidays and a week of being ill mean I didnt get far with it.

Anyway, pulled the airbox off. got down to the coils, #1,2 and 4 pop straight off, #3 lifts up but wont pop off properly. End up getting mole grips onto it. have someone hold the bike down while i yank it out. See the pics below

Coil has pretty much exploded and taken out the spark plug or vice versa. I've pulled the other plugs and they all look relatively ok so I assume coil failure. I was having a slight missfire recently having ridden a lot in the wet. Ive got 95% of the sparkplug, the vast majority of the ceramic and have about 5-10% of the electrode unaccounted for. The plug itself had popped out and been wedged by all the ceramic and bits of coil so thankfully doesnt appear to have gone through the engine. I've still not got round to doing a compression test which I plan to do tomorrow. I've spent almost a fortnight trying to find a 10mm backtap. For some reason we cant get them in the UK? Only ones I have seen are listed in the US with about a fortnight delivery time. Instead I've had to opt for a standard chaser to clear the thread. Im not planning to pull the head of assuming the compression is ok. I cant really justify making such an outlay on getting work done on a relatively old bike unless it justifies it. 

There doesnt appear to be any issue with the inlet valves having looked down the throttle bodies. A compression test should show tomorrow

Pics are in no particular order, apologies if you have slow internet theyve come straight from my phone

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I can't see how a coil can explode or cause that much damage.
The only things I can think off, is that the plug was not tight and you've had hot gas bypassing and melting everything.
Or debri inside the cylinder smashing the plug and burning everything else.
A hole in your piston would explain all the oil in the air box.

Yup, that's quite freaky, what happened there.....
Possibly, the mechanic did not tighten the plug adequately and it loosened to the point where the cylinder ignition gasses and explosive pulses was beating up on and burning the coil and plug as mentioned on the previous post till things just eventually blew up to smithereenies......
You might have a good case against the shop that worked on your bike, as long as you can prove/convince them that you did not touch that plug and coil after they worked on it....

I've never seen anything like it. 

When was the last time you had the plugs changed?

I to, have never seen anything like it

Same thing happened to my 2006 Honda Ridgeline, garage put heli-coil in and must have gotten chips into cylinder. Rebuild and $7000.00 later all is good!!

I'd be real worried about debris in the cylinder with that kind of deconstruction to the plug.

So since it ran great I'm assuming before the valve check, why go through all this and not take it back to said mechanic who obviously screwed up somehow, especially after spending...what $7-800 dollars, atleast that's what they want here in Cali. Good luck

Did it  blow a  spark  plug  out ?

Hmmmm     !!!!!!!!!!

SuperBeef you're getting a lot of amateur speculation here  with no actual troubleshooting procedure.

Yeah  I  only  have  40  years  of  owning, working on  motorcycle's and  was  ASI  certified  for  20 year.

Pfft! Is that all?! 

Yep  sorry .

Make that 41 years !!!!!

So since it ran great I'm assuming before the valve check, why go through all this and not take it back to said mechanic who obviously screwed up somehow, especially after spending...what $7-800 dollars, atleast that's what they want here in Cali. Good luck

It was a valve check only, no fluids/plugs/filters. I planned on doing all of that myself once I had it back.

When was the last time you had the plugs changed?

I to, have never seen anything like it

I havent since I owned the bike, but with FSH up to the last 4k I assumed ok when I bought it. I had another set of plugs to put in, which I planned to do once I had it back from the valve check, at the same time as fitting a power commander and sorting a few other issues out.

In the cylinder I found a coiled piece of metal, the same pitch as the thread on the plug. Presumably a failed helicoil

Really stinks that you're sort of stuck with a "who done it".


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It looks like the electrode and insulator came off inside the cylinder,that plug look REALLY old too.

When I got my VFR I found the plugs not even finger tight after a couple of tanks of bad mileage,I think it would have to be barely threaded to have something like that happen.

I would try to get my money back from that shop,pull the head and hope there was only bent valves in there.Then I would buy a good used head and take it somewhere else to get it put in or just replace the engine if there is piston damage.

Really stinks that you're sort of stuck with a "who done it".


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Potentially the helicoil has been disturbed when the plug was removed and then it hasn't seated back down.

It looks like the electrode and insulator came off inside the cylinder,that plug look REALLY old too.
 
When I got my VFR I found the plugs not even finger tight after a couple of tanks of bad mileage,I think it would have to be barely threaded to have something like that happen.

I'm going to go in and speak with them in the week. Looking at the plugs the washer is corroded and can't imagine it forming a good seal. What stopped me changing the plugs sooner was waiting for an air filter and power commander to turn up. The plan was to get it all done in one hit. It a difficult to say whose fault it is, garage for not putting the plugs in properly or myself for not changing them. That said I'm not really sure why they put them back in and didn't say anything. Ill see what happens Monday and go from there

Good luck   ...

Hey Look, my picture doesn't take up the whole page!!!  :goofy:

You are right, "only" about a third.....   still way too big...