Technical Multijet rattle

[puntodad19]

100mph on a super slug 250, only down hill with a tail wind on a dead straight bit of road, and a bit of luck.

He said that the speedo needle wildly s ki
wung between 85 and 105 so i reckon he Did achieve the ton, in his head.

Still got that bike, tax/mot exempt. Emergency emergency standby transport....

 

[bugsymike]

100mph on a super slug 250, only down hill with a tail wind on a dead straight bit of road, and a bit of luck.

He said that the speedo needle wildly s ki
wung between 85 and 105 so i reckon he Did achieve the ton, in his head.

Still got that bike, tax/mot exempt. Emergency emergency standby transport....

"Back in 1978, speed-crazed teenagers were excitedly taking to the road on Suzuki’s latest learner-bike – advertised as “the new ‘Ton-up’ GT250 X7”."

 

[puntodad19]

suzy super six......in the sixties....

 

[bugsymike]

suzy super six......in the sixties....

It was the kids having accidents on the X7 that got the press calling for the new laws.

 

[DaveMcT]

The 400 made a claimed 43 bhp. It was certainly quicker than my Kwak which had only 37bhp. But the engine were cheaply built. The timing chains did what Hondas of the day usually did (crapped out in 20,000 miles). The real nasty was balance shafts that carried everything on the cush drive rubbers. The (not inconsiderable) forces wrecked the rubbers which then took out the roller chains. I assume the 250 was the same setup but maybe the slightly less weight to counteract was just within the design limits.

My favourite Honda was an XL 250 K0. The original with silver tank and LHS exhaust pipe. They are a small fortune today.

 

[puntodad19]

Roller chain, rollerless ie solid non rolling rollers from memory. I will check over the weekend.

The cush drive type balance weights, cush segments ( rubbery type material ) go rock hard and cause "play" in cush dive weight and sprocket.
Sprockets have been known to break up.

The four centre head bolts can be a real nightmare to remove. The really dumb honda method, built on seals to cure a designed in oil leak unless new bolts used. Many owners us sealer to cure oil leak, but sealer entering bolt hole causes upper crankcase bolt hole to burst the casing. Ignorence about a mear lick of sealer on rocker carrier to head interface caused oil leak "up stairs". Owners putting wrong bolts in wrong holes ruining c/case bolt holes and burst casing.

Not cleaning out centre bolt holes properly using a 10 X 1.25 plug tap etc. etc.etc......

 

[DaveMcT]

Fiat Multijet still has a "catch out the unwary" M8 bolt issue. The cam carrier is longer than the cylinder head with (an obviously added in CAD) extra on the end to carry the air pump and diesel injection pump. Adding the extra bit to the cylinder head gearbox end was obviously too much trouble.

The result is the air pimp lower retaining bolt (M8) has to be the absolutely correct original item. When the correct 21mm long bolt is fully screwed in, there's 1mm clearance between bolt end and cylinder head. Use the wrong bolt and you will jack the crappy bracket off the end of the cam carrier. Ask me how I know?

The problem is that access is horrible and you cannot see what is going on. The force needed to crack the casting is considerably less than needed to normally tighten the bolt.

 

[DaveMcT]

So that 312 has been an absolute B*TCH to wark on. The 169 is a dream (yeah right) in comparison, but the 312 makes everything hard work.

I had it assembled and ready to test run. On starting, it made the most horrible clatter. The hassle of fitting the cam cover had me worried a valve rocker had been dislodged. So I pulled it all down and of course the rockers were all sitting nicely. At least, I got chance to fit a new oil pump and cover. The old (new) crank seal was leaking and a new cover-cum-oil pump is not silly money.

To be fair, this is not Fiat's fault... Replacing the sump I found half of the (M6) bolts had been stripped out. That's down to the monkey with a zip driver who replaced the sump last time. Thankfully it's secure enough for now, but they'll have to be tapped out to M7 (hopefully).

Everything is awkwardly installed and absolutely has to be done in the right order. Get it wrong (as you will) and you'll be doubling the work.
The aircon condenser is screwed to the front of the engine radiator but the screws are those nasty quick rust self tappers that Fiat use for the wheel arch liners. They all had to be slotted with a Dremel disc. One has sheared off - who knows how I'll get that out. The others I've tapped M5 for stainless screws.

The radiator frame is steel. Fair enough it's stronger than plastic, but the paint is even worse at stopping rust than the stuff they use on rear axles. Radiator brackets are horrible folded steel with the same quick rust paint. They have to be unbolted from the main frame making refitting a struggle on your own.

The main structural front bumper has four M10 bolts at each side. It traps the radiator frame, so you now have to hold up that lot while not cross-threading the M10 fine bolt. The lower bumper is even worse. You can't get a socket extension to the job without cross threading. Then you find it's on the wrong way around. Everything seems designed to make the job hard work.

 

[DaveMcT]

The engine is still not right and wont run with the MAF connected. It clattered just the same on start-up but this time I let run and settled down. I never knew a lazy tappet/lifter could be so noisy! The engine is still running on three and now even more lumpy, so (as before) I'm expecting it to need injectors. A check of codes etc will help with that. All four injector tips look dry, so I was hopeful it would be ok, but it seems not.

Tomorrow will be an MES session. Clear the codes and see what turns up. Hopefully, I wont need any paid for features.

 

[DaveMcT]

It got there in the end. First start sounded horrible. Following morning, it started just fine and ran well. I can only guess it was air in the fuel system. The MAF issue was me leaving the turbo outlet air hose disconnected. D’Oh!

MES shows no code issues and injection pressure is correct at idle speed. I didn’t check it at higher revs.

So job done. Car is running smooth & quiet.