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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • 1994 - 1995 Specific Tech

i THINK MY BRAND NEW 306 BLEW UP!!!!!

  • Thread starter Thread starter Pokageek
  • Start date Start date Jul 17, 2005
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Pokageek

Active Member
Jun 10, 2005
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46
MA, USA
Jul 17, 2005
#1
  • Jul 17, 2005
  • #1
Thanks to your suggestions, I got the idle working great. I was very happy.

BUT about 30 miles into my test ride the car started sputtering up hills or when under load and now it sounds like someone is hammering inside the engine that gets louder and faster with any increase in RPM or load. It also loses power up hills and I barely made it home. No smoke, the oil pressure is still very good (no change) no overheating but something mechanical must be horribly wrong! Even at idle it sounds terrible like a hammering on one side of the engine like a bad piston or valve or rod or something!

I can't begin to describe how SICK I feel over this. I spent $1000 to have this engine put in and spent hours of sweat and time helping put it in myself. I was going to check and make sure a spark plug boot wasn't loose or something but the wires were so hot that I couldn't even touch them. Is this normal from the headers? It didn't seem right. I think it is toast. I did not run it past 3500 all night, and did all the proper maintenance and fluids and no leaks.
 
W

wytstang

Mustang Master
Mar 14, 2004
4,988
4
78
Summerville,SC missing South Fl. weather :(
Jul 17, 2005
#2
  • Jul 17, 2005
  • #2
If it's knocking then close the hood and walk away it's done. Sound like it throw a rod, and if I remember correctly this engine is new and should have a warrenty. I think I'm the one who asked you why you were going with such a cheap builder well this is why. Sorry to hear the bad new man good luck.
 

Pokageek

Active Member
Jun 10, 2005
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Jul 17, 2005
#3
  • Jul 17, 2005
  • #3
It has a 12 month 18k mile warranty. As to the company, it has been around for 20+ years and a knowledgeable sales staff. I paid $1800 for it discounted from $2200. I did the research as you suggested about the internals. It was align honed, decked and put together with ARP rod bolts The heads were a bit waek being it has "re-ground " valves or something. All considered I don't think it was cheap though and felt very comfortable with their staff. They seem to be good honest people. I will be calling them on Monday after we look at it once more. I am very disappointed right now after all the time put in though.

BTW, what exactly is a "thrown" rod? What does that mean and how might that happen? Thx.
 

donjohn

New Member
Feb 7, 2004
1,757
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0
Irvine - Southern California
Jul 17, 2005
#4
  • Jul 17, 2005
  • #4
i wouldn't disagree, if you've got the knocking

don't drive it anymore, and make sure it's not the harmonic balancer although it doesn't sound like it some of it's symtoms are present
 
G

Green 94 5.0

Founding Member
Mar 25, 2002
2,601
12
79
Ft. Lauderdale, FL
Jul 17, 2005
#5
  • Jul 17, 2005
  • #5
if it was the harmonic balancer, the car would shake violently. this definitely sounds like something far worse. hope everything works out for you.
 

donkey_punch

New Member
Jan 16, 2004
565
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northern****ingjersey
Jul 17, 2005
#6
  • Jul 17, 2005
  • #6
i have a couple of stupid question. you have flat top pistons im your sig.
did you see the top of the new pistons?
did they have valve reliefs cut into them?
or did you have the heads or block milled?

another question that has to do with timing
i take it you made sure when you put the distributor in you had the motor at top dead center, on the right revolution? your timing could be off 180*.
i speak from experience it will have no power, and make god awful noises when trying to drive it.
 

94GTLaserRC

Squint as you approach, lest you be blinded by my
15 Year Member
May 7, 2002
11,178
13
89
Ernan Says "here it comes... dushbag"
Jul 17, 2005
#7
  • Jul 17, 2005
  • #7
Subscribing...curious to find out what it is.

RC
 

YEAHLOH95

Founding Member
Nov 19, 2001
1,249
3
39
EVERETT,PA
Jul 17, 2005
#8
  • Jul 17, 2005
  • #8
could it be a rocker ????
 
G

Green 94 5.0

Founding Member
Mar 25, 2002
2,601
12
79
Ft. Lauderdale, FL
Jul 17, 2005
#9
  • Jul 17, 2005
  • #9
just by the way he describes it, i doubt it is a rocker. i hope for his sake though that it is something as simple as that.
 

sociopath5.0

New Member
Jul 7, 2004
155
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somewhere near Louisville, KY
Jul 17, 2005
#10
  • Jul 17, 2005
  • #10
Good luck, man. Since mine is getting closer to running, I'm a little nervous now. I hope your trouble is not something serious or fatal.
 

Joes95GT

New Member
Jan 23, 2003
3,132
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Delaware
Jul 17, 2005
#11
  • Jul 17, 2005
  • #11
Green 94 5.0 said:
just by the way he describes it, i doubt it is a rocker. i hope for his sake though that it is something as simple as that.
Click to expand...
Me too.

I'd bet money that it's either spun rod bearing(s), or it's beating one of the main bearings out. Either is not good...

Joe
 
S

Synned

took tubgirl on a date and got banned
Mar 31, 2005
991
1
0
Philly
Jul 17, 2005
#12
  • Jul 17, 2005
  • #12
another question that has to do with timing
i take it you made sure when you put the distributor in you had the motor at top dead center, on the right revolution? your timing could be off 180*.
i speak from experience it will have no power, and make god awful noises when trying to drive it.
Click to expand...

Well he did have it idling right so I don't think its timing.
 
W

wytstang

Mustang Master
Mar 14, 2004
4,988
4
78
Summerville,SC missing South Fl. weather :(
Jul 17, 2005
#13
  • Jul 17, 2005
  • #13
Pokageek said:
BTW, what exactly is a "thrown" rod? What does that mean and how might that happen? Thx.
Click to expand...
It should have read thrown rod bearing, basicly the bearing is spun and wiped out (down to the copper) and now is fubar.
 
B

bimmertech

New Member
May 3, 2005
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0
merriam, ks
Jul 17, 2005
#14
  • Jul 17, 2005
  • #14
Synned said:
Well he did have it idling right so I don't think its timing.
Click to expand...
i just bought a 94 that idled fine, but when the timing came in it would knock like all hell. i pulled the spout and it works fine now. funny cuz i bought it cheap thinking it needed a motor . i would say that if his knoking is coming in at 2200 then it is most definetly a timing problem and not a mechanical issue. if the knock is at idle and everywhere else, well back to the drawin board.
 

Pokageek

Active Member
Jun 10, 2005
2,767
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46
MA, USA
Jul 17, 2005
#15
  • Jul 17, 2005
  • #15
Thanks for the suggestions.

"another question that has to do with timing
i take it you made sure when you put the distributor in you had the motor at top dead center, on the right revolution? your timing could be off 180*."

Yep this was checked. It is at idle and at speed.

"did they have valve reliefs cut into them?"

I don't know.

"or did you have the heads or block milled?"

No not milled. New harmonic balancer.
 

5.0_GT_kid

20+ Year Stangneter
Apr 18, 2004
1,155
1
39
Largo, Florida
Jul 17, 2005
#16
  • Jul 17, 2005
  • #16
Well whatever happens, good luck with it buddy.
 

S/CBlack95GT

New Member
Apr 6, 2003
2,018
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0
Tampa Palms, FL
Jul 17, 2005
#17
  • Jul 17, 2005
  • #17
I had a really bad knock with my engine once. Sounded like a spark knock/rocker arm knock. Turns out the plug wire boot came off the spark plug and the spark was arcing about 1 inch between the spark plug tip and the wire contact. It made one heck of a noise.

Just make sure to check the simple stuff first.
 
S

stang_dan

Founding Member
Aug 27, 2001
172
0
0
new jersey/north caroline
Jul 17, 2005
#18
  • Jul 17, 2005
  • #18
just out of curiousity whats the name of the company you bought the motor from.
dan
 

Blk05Retro

Member
Mar 31, 2005
99
0
6
Katy, TX
Jul 17, 2005
#19
  • Jul 17, 2005
  • #19
It could be some serious detonation. You said that your spark plugs wires were extremely hot. You should pull the spark plugs to see what conditon they are in. With really bad detonation, you can burn the ends clean off. I would think that the wires would get hot in the condition you described.
 

Pokageek

Active Member
Jun 10, 2005
2,767
0
46
MA, USA
Jul 17, 2005
#20
  • Jul 17, 2005
  • #20
Blk05Retro said:
It could be some serious detonation. You said that your spark plugs wires were extremely hot. You should pull the spark plugs to see what conditon they are in. With really bad detonation, you can burn the ends clean off. I would think that the wires would get hot in the condition you described.
Click to expand...

Thanks guys. I will check this. I was also unimpressed with the power from this motor to boot. I didn't hit it hard but got a feel for it. I am calling them tomorrow is the spark plugs look ok.
 
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