94 Vmax4 Engine ??

True Blue

True Blue

New member
Hello everyone,


Need someone with engine experience to help me with an issue of no power. It starts and idles fine from what I can tell but when you gas it its slow to pickup no snap to it at all. Last thing that happened was I busted a belt at top speed and now I wonder if I got cranks out of phase? Can you
tell by the sound if the engine if it's out of phase or will it even run at all ? I'd like to add a video on here and have someone tell me if it sounds normal but I don't see how to add a video.


Thanks
 
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The whole crank out of phase issue is way overplayed. What kind of belt did you replace the blown one with? The majority of issues you describe are clutching. There is not enough information here to diagnose accurately.

Applying logic, if the sled ran fine before blowing the belt and the belt is all that was changed, that is the issue. Old belt, worn used belt? Dirty clutches. Sticky residue on the clutches. Worn clutch components, belt deflection is off. Clutching is the first place to start. There is a reason the belt blew in the first place.

Good luck.
 
Ok it's been a while and the unit has been in storage. I will look into the clutching but is there an easy way to check phasing? I'm reading for stock motor the Clutch side should be TDC and the recoil side those two should be 1/2 way in the cylinders if so what about the one next to the TDC one ? Thanks
 
True Blue said:
Ok it's been a while and the unit has been in storage. I will look into the clutching but is there an easy way to check phasing? I'm reading for stock motor the Clutch side should be TDC and the recoil side those two should be 1/2 way in the cylinders if so what about the one next to the TDC one ? Thanks
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its not overplayed, i have had it happen 3 times, i have had just the gear jump one tooth and the other time the gear twisted on the shaft. both halves are indexed at 180 so one tdc next is bdc and the next two will be the same. if the last two are not identical well, you got a busted max.
 
Busted Max said:
its not overplayed, i have had it happen 3 times, i have had just the gear jump one tooth and the other time the gear twisted on the shaft. both halves are indexed at 180 so one tdc next is bdc and the next two will be the same. if the last two are not identical well, you got a busted max.
Click to expand...
 
It is overplayed. The gears don’t jump. High rpm harmonics have been known to cause some movement of gears due to the mild press fit on the individual cranks. This will cause a timing issue. That’s why some race engines had gears tack welded. I’ve been around scores of these engines since they first came out. Still have five of them. One of them is 180.
The concern I have is for years, as soon as someone was disappointed in their Vmax4 performance, they were told the crankshaft was probably out of phase. This was before the person even tried changing drive belts.

The way to check on a 90 degree ( stock crankshaft) is to get a good dial indicator setup. While sittting on the sled, refer to cylinders 1-4 from left to right. When number 1 is at TDC, cylinder 2 is at BDC. Cylinders 3 and 4 will be parallel. If these measurements don’t correlate, you have indexing issues. Busted has in right Looks like the OP may have an issue.
 
Forgot to mention; be sure the number 1 cylinder is exactly at TDC. You need an indicator. You may have done that, sorry if I’m questioning. Remember, 3 and 4 are traveling in opposite directions as the crank rotates. A very slight rotation while checking gets them apart real quickly. There is some tolerance too. Piston crowns can have very slight variability as well.

I’ve always tried to help people on this site. Nothing I suggest is bullshit. It all comes from learning the hard way.



Good luck.
 
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