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toylux 09-05-2013 01:57 PM

thanks again :) didn't get anything done today, pouring down outside :/
i do not know what igition system it is but it looks like it is the originale. and on metal thing between the rockers it says "mark v" if that can tell anybody what year or ignition system it is?

:)

Svein

babalu 09-05-2013 02:45 PM

find ignition module on the engine and see what is written on it , can be mounted on distributor or port side exhaust elbow
thunderbolt IV is a single module no special procedure for timing
thunderbolt V usualy two modules mounted on distributor , needs purple white wire connected to ground to set timing and carb adjustment

blue thunder 09-05-2013 06:28 PM

Gen 5 a mid ninties is probably a tbolt 5 ign. The purple/white wire that you need to ground runs between the ig module and knock sensor module and has a pigtail to ground, often with a rubber plug in it that you remove when grounding.

Greatguy66 09-05-2013 08:18 PM

Ignition or kill switch?????

toylux 09-08-2013 08:59 AM

hi again :) it is finally sun again and i've don a little on the boat. it is a TBV ignition on it i think, it has the two modules on the distributor.
i pulled the valve cover and all the rockers were tigthend almost all the way in :O when i adjusted them the chugging was gone :D but i saw that one of the pushrods where sligthly bendt. :/
on full thottle she still backfires but i have not adjusted the timing with the white purple wire grounded yet. i hope i got time for that tomorrow.
any thougts? :)

best regards.

Svein Rønningen

Payton 09-08-2013 09:18 AM

You better find out what bent that pushrod. Still could be a cam lobe.Replace and check that each lifter has same amount of movement.

ratman 09-08-2013 10:47 AM

that is a heavy boat, but a nice one. spend a few bucks. pull the heads and get a valve job done, install a roller cam, and msd ignition.... they are heavy and need a strong engine to wake em up!

toylux 09-08-2013 02:02 PM

if it's not helping with an adjust of the timing tomorow is it only cam or coil left that can be wrong? if so what brand type is the one to choose? engine parts are extremely pricy here so i would prefer to have something reliable but not too pricy.

best regards

svein rønningen :)

fleg1 09-08-2013 02:23 PM

If the rockers were adjusted to tight, could have started to round the lobes on the cam..

ratman 09-08-2013 05:55 PM


Originally Posted by toylux (Post 3990692)
if it's not helping with an adjust of the timing tomorow is it only cam or coil left that can be wrong? if so what brand type is the one to choose? engine parts are extremely pricy here so i would prefer to have something reliable but not too pricy.

best regards

svein rønningen :)

set up a paypal account and buy the stuff on ebay in the states. figure a way to get it shipped to you before you buy. the good thing with roller cams is used ones work fine unlike a flat tappet cam. a msd blaster 2 coil is cheap and produce a h3ll of a hot spark, get someone that knows these engine to set the heads up properly for the cam you buy, the correct spring pressure is very important. i would buy a set of good valve springs to go with the cam. you can make a lot better hp and tq with a roller cam, they open the valve much more quickly, so it is at maximum lift much longer... that is a killer boat. post up some pics...rm


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