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Message |
    
richie phillips
Member
Username: mustangturbo50
Post Number: 8
Registered: 03-2009
| | Posted on Thursday, June 18, 2009 - 07:40 pm: | 
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ok so last year my boat ran great last year , so i got it out this year and found that i had left a little water in the exhaust manifold so it cracked it a little, not bad but a little, so i had it fixed and took it out the water and it started and reved up great in neutral , i put it in gear and started to go out of the harbor and it just wont go over 5 mph, if i go more than 1/4 or 1/2 throttle it bogs down and just wont go. i took the old gas out and put new in, checked the oil for water and everything looks great, so i dont now think anything is cracked anywhere. The odd thing is that if i let off the throttle and put it in neutral it revs right up no hesitation no nuthing, just revs up liek it is supposed to.
i check compression in all the cylinders and it is 92 lbs all the way accross , all the same.
if anyone has any advise let me know
im leaning more tords a carb issue but i could be wrong. i think it is just a coinsidence that it happens to be running like this since the manifold froze |
richie phillips
Member
Username: mustangturbo50
Post Number: 9
Registered: 03-2009
| | Posted on Thursday, June 18, 2009 - 09:15 pm: |
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and i forgot to mention when i try to make it go faster it just bogs like there is not enough fuel. |
Robj
Advanced Member
Username: robj
Post Number: 140
Registered: 09-2007
| | Posted on Friday, June 19, 2009 - 08:44 am: |
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Compression should be over 150 lbs, 92 lbs is WAY TOO low. Time to do a leak down test to see what is going on.
Have a great day
Rob. |
richie phillips
Member
Username: mustangturbo50
Post Number: 10
Registered: 03-2009
| | Posted on Friday, June 19, 2009 - 08:48 am: |
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it will hold 92 lbs for an hour does not leak down. is it possible it has jumped time a little.? |
richie phillips
Member
Username: mustangturbo50
Post Number: 11
Registered: 03-2009
| | Posted on Friday, June 19, 2009 - 08:50 am: |
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it the valves are not opening when they are supposed to for long enough to suck in enough air for compression? |
Robj
Advanced Member
Username: robj
Post Number: 141
Registered: 09-2007
| | Posted on Friday, June 19, 2009 - 03:47 pm: |
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I don't understand the hold 92 psi part. Has nothing to do with a compression test. And yes it could be a skipped timing belt.
Have a great day
Rob. |
El Pescador
Senior Member
Username: el_pescador
Post Number: 4514
Registered: 02-2006
| | Posted on Friday, June 19, 2009 - 04:00 pm: |
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I agree with Robj, the timing belt could have jumped, as 92 psi compression (if the gauge is working correctly) is way too low. If this is not the problem, you may have an accelerator pump not doing its job. |
richie phillips
Member
Username: mustangturbo50
Post Number: 12
Registered: 03-2009
| | Posted on Friday, June 19, 2009 - 06:27 pm: |
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so your saying it could just be out of time? anyone have a link to timing marks, i do not have a shop manual. and yes 92 is way to low i know. and it does have to do with the compression test because if it got to 150 and blead down if 2 sec that woudl be an issue. but it is just so odd that it is hold 92 lbs on all but one cylinder and it is 91 lbs. and the gage is brand new. i tried to dif gages |
Robj
Advanced Member
Username: robj
Post Number: 142
Registered: 09-2007
| | Posted on Friday, June 19, 2009 - 11:08 pm: |
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I have never heard of a compression test bleed down. My guess your gage holds the 92 psi, not your cylinder. With a compression test you crank the engine, with the carb butterfly wide open until you get a max reading on your gage. Usually around 4 to 6 revs. Just crank until the pressure does not change. I really doubt that a cylinder will hold 92 psi for an hour. Never tried but I would think the pressure would bleed down much faster than that.
Have a great day,
Rob. |
richie phillips
Member
Username: mustangturbo50
Post Number: 13
Registered: 03-2009
| | Posted on Friday, June 19, 2009 - 11:17 pm: |
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but my concern is why it only has 92lbs, it is just to odd that it is on all 4 cylinders? could it be a tooth off on timing? it wouldnt wash all the rings out the same if it where just time for a rebuild. it must be out of time. any thoughts? |
Robj
Advanced Member
Username: robj
Post Number: 143
Registered: 09-2007
| | Posted on Friday, June 19, 2009 - 11:29 pm: |
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Check your timing belt. That could very well be your problem. If you don't have a manual, get one but in the meantime, align the crank to 0 on your timing marks, then see where the cam is. There is a mark on the top that should be at 12 o'clock. Your rotor should be at No. 1.
Have a great day
Rob.
Have a great day
Rob. |
richie phillips
Member
Username: mustangturbo50
Post Number: 14
Registered: 03-2009
| | Posted on Friday, June 19, 2009 - 11:31 pm: |
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ok thanks. i meant leak down when i was saying leaking sorry. i got mixed up. ill check it tomorrow. crank to 0 timing mark on timing cam lined up with the notch in the plate behind it right? |
richie phillips
Member
Username: mustangturbo50
Post Number: 15
Registered: 03-2009
| | Posted on Saturday, June 20, 2009 - 11:54 am: |
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Ok so today i took the old belt off and put a new timing kit on it from gates and i rechecked compression and it is at 150 now. so im thinking i got it whipped.
i did check the timing and it was 2 teeth off and the belt was stretched pretty bad.
im wondering if it was a tooth off last year because it just didnt seam to have any power and it would only go like 25 mph which it should do at least 40 i would think. i could be wrong. but it is only 18 ft and that seam like it would be faster than 25. correct me if im wrong |
Robert A. Fierro
Advanced Member
Username: sandkicker
Post Number: 614
Registered: 06-2008
| | Posted on Saturday, June 20, 2009 - 12:28 pm: |
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You're lucky... often when the timing is off and you have low compression, and the engine gets run that way, then next thing that happens is burned valves. |
